GAMSAT Section III Chemistry - Part 1

	Your Score	Average of all Users	Percentile
Chemistry - Part 1

Speed as well as accuracy is important in this section. Work quickly, or you might not finish the paper. There are no penalties for incorrect responses, only marks for correct answers, so you should attempt all questions. Each question is worth one mark.

You must complete the answers within the time limit. Calculators are NOT permitted.

Good Luck!

ELECTROLYSIS AND ELECTROCHEMICAL CELLS

A salt bridge (figure 1) is essential in maintaining electrical neutrality in an electrochemical cell. Without a salt bridge, the two different compartments will accumulate the opposite charges and limit any further reaction.

2Ag⁺(aq) + Cu(s) →2Ag(s) + Cu²⁺(aq)

Source: https://www.google.com/url?sa=i&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FSalt_bridge&psig=AOvVaw1a73VARICqE05QmAhSplbO&ust=1623536168771000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCOCcmunNkPECFQAAAAAdAAAAABAD

1. For the salt bridge to function adequately, an appropriate electrolyte must be present. Read the following statements A-D. Which of them provides the most accurately explains whether or not the appropriate electrolyte is used in the following electrochemical cell?

A. KOH is inappropriate because potassium has a very positive reduction potential

B. CuS is appropriate because neither the cation or anion will react with the ions in the compartments

C. K₂SO₄ is inappropriate because polyatomic ions like the sulphate ion will oxidise more easily than water will

D. KCL is inappropriate because it will react with the ions in the compartments

10

7

Explanation

The correct answer is D.

KCl would be a good choice normally because it does not react with any of the chemicals used in the cell, and the anion and cation have similar conductivity, and hence similar migratory speed. In this case, since one of the ions is silver and silver chloride is insoluble, a KCl bridge is not appropriate.

Post Comment

STD Medicmind Tutor

Thu, 01 Aug 2024 12:56:25

Well, there's no silver in your diagram...

ELECTROLYSIS AND ELECTROCHEMICAL CELLS

Figure 2 shows a galvanic and electrolytic cell.

Source:https://www.google.com/url?sa=i&url=https%3A%2F%2Fchem.libretexts.org%2FBookshelves%2FAnalytical_Chemistry%2FSupplemental_Modules_(Analytical_Chemistry)%2FElectrochemistry%2FElectrolytic_Cells&psig=AOvVaw1mbMAYn9LdGQX2qYHNJVYq&ust=1623537579207000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCOjQ4obTkPECFQAAAAAdAAAAABAD

2. Which of the following accurately describes the difference between galvanic and electrolytic cells?

A. The flow of electrons goes from the anode to the cathode for galvanic cells

B. Oxidation occurs at the negative terminal, and reduction occurs at the positive terminal for an electrolytic cell

C. Electrolytic cells have a positive EMF and positive ∆G° such that it requires an external battery source to drive electrons

D. The anode is the negative terminal for a Galvanic cell because the anode is the source of the electrons where oxidation occurs

5

0

Explanation

The correct answer is D.

Galvanic cells have the anode as the negative terminal and cathode as the positive terminal. Here, the signage comes from the anode providing the electrons for the circuit through oxidation.

Post Comment

ELECTROLYSIS AND ELECTROCHEMICAL CELLS

Figure 2 shows a galvanic and electrolytic cell.

Source:https://www.google.com/url?sa=i&url=https%3A%2F%2Fchem.libretexts.org%2FBookshelves%2FAnalytical_Chemistry%2FSupplemental_Modules_(Analytical_Chemistry)%2FElectrochemistry%2FElectrolytic_Cells&psig=AOvVaw1mbMAYn9LdGQX2qYHNJVYq&ust=1623537579207000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCOjQ4obTkPECFQAAAAAdAAAAABAD

3. Which of the following statements accurately describes an electrolytic cell?

A. Alkali or alkaline earth metals, which are the cations of the electrolyte, do not get oxidized in an aqueous solution since water is more easily oxidized

B. Polyatomic ions, which are the anions of the electrolyte, are typically more easily oxidized than water

C. For aqueous solutions of the electrolyte, a gas may be produced at the anode

D. In both molten or aqueous forms, the cation will be reduced and the anion will be oxidized.

3

2

Explanation

The correct answer is A.

Ultimately, the anion of the electrolyte will get oxidized, but water would be more easily reduced than most metals. When it gets reduced, hydrogen gas is produced at the anode.

Post Comment

z Medicmind Tutor

Tue, 03 Jan 2023 04:46:00

why is c wrong. gases can be produced at the anode; gases be oxygen

ELECTROLYSIS AND ELECTROCHEMICAL CELLS

Zn(s) + 2H⁺(aq) → Zn²⁺(aq) +H₂(g)

4. The following equation has an equilibrium constant (Keq) of 6×10²⁵. Which of the following correctly describes the standard electrode potential E°, and the standard Gibbs free energy change (∆G°)?

A. ∆G° is negative, ∆E° is positive

B. ∆G° is positive, ∆E° is negative

C. Both ∆G° and ∆E° have the same sign

D. Both ∆G° and ∆E° are zero

2

1

Explanation

The correct answer is A.

The equation tells us that the greater the standard electrode potential, the more negative the standard free energy change. So the correct answer is that ∆G° is negative, and E° is positive.

Post Comment

z Medicmind Tutor

Tue, 03 Jan 2023 04:48:44

this is wrong. the standard electron potential of zn/zn2+ is -0.76v. it is also negative

jenny Medicmind Tutor

Mon, 03 Jul 2023 15:05:18

can someone explain this in more detail - why does the equation show that ?

HAMDA KHAN Medicmind Tutor

Tue, 12 Sep 2023 10:42:19

G=-NFE

chloe Medicmind Tutor

Wed, 03 Jan 2024 12:11:25

it is asking of the standard electrode potential of the whole reaction (the voltage generated if the reaction were to occur). the E0 of Zn/Zn2+ is -0.76V and the E0 of H2/H+ is 0.00V. the standard electrode potential (of reaction) is calculated by the E0 of the oxidant deducted by the E0 of the reductant. thus, standard electrode potential is 0.00 - (-0.76) = +0.76V.

Amino acids and proteins

5. Which of the following amino acids will have a negative charge at physiological pH (7.4)

A. Histidine

B. Lysine

C. Asparagine

D. Glutamic acid

4

Explanation

The correct answer is D.

Acids carry a negative net charge.

Post Comment

Amino acids and proteins

6. For a polypetide to have a net positive charge at physiology pH what R group does the amino acid mostly like contain?

A. Acidic R groups

B. Aromatic R groups

C. Basic R groups

D. Aliphatic R groups

1

0

Explanation

The correct answer is C.

For something to have a positive charge it must have a basic R group.

Post Comment

Amino acids and proteins

7. Which of the following is least likely to be affected by changes in pH?

A. The tertiary structure of a protein

B. The primary structure of a protein

C. The secondary structure of a protein

D. The net charge of the protein

0

Explanation

The correct answer is B.

pH is least likely to affect how proteins are formed and amino acids are bonded together, they are more likely to affect the later aspects of protein structure.

Post Comment

jenny Medicmind Tutor

Mon, 03 Jul 2023 15:07:42

how does pH affect the net charge of a protein ?

chloe Medicmind Tutor

Wed, 03 Jan 2024 12:05:34

protein is made up of amino acids which have different side chains (called R groups). these R groups could be anything ranging from non polar hydrocarbons to consisting of carboxylic acid groups. eg, in high pH enviro, the acid would deprotonate, which forms COO-, hence the protein's net charge will change.

Amino acids and proteins

8. The hydrogen bonds present between separate subunits of DNA polymerase is an example of which of the following?

A. 1st degree structure

B. 2nd degree structure

C. 3rd degree structure

D. 4th degree structure

1

Explanation

The correct answer is D.

1st, 2nd and 3rd degree structure all pertain to the specific protein, 4th degree structure is that between multiple peptides.

Post Comment

Atomic structure

9. Nitrogen is found 70% of the time as Isotope 147N and 30% of the time as 127N. What is the correct atomic mass of nitrogen in light of this?

A. 13.8 amu

B. 13.5 amu

C. 12.8 amu

D. 13.4 amu

0

26

Explanation

The correct answer is D.

Post Comment

Stephanie Medicmind Tutor

Thu, 27 Jan 2022 23:06:14

Why is the answer D? 0.7*147 + 0.3*127 = 141

Sam Medicmind Tutor

Tue, 08 Feb 2022 13:20:33

I agree with Steph. Answer should be 141

Harriet Medicmind Tutor

Tue, 09 Aug 2022 13:39:38

Could someone explain how they achieved this answer?

Bec Medicmind Tutor

Sun, 04 Sep 2022 01:23:00

It should be 14-N and 12-N... 7 is the subscript as its the atomic number... They got the format wrong. Thus its D.

Ethan Medicmind Tutor

Sun, 19 Mar 2023 03:58:33

it should be 14*0.7+12*0.3=13.4, the 7 in 147 and 127 were suppose to be the atomic number, they messed up the superscript and subscript

Atomic structure

10. There are 64 atoms of unstable Polonium isotope in a closed container. The half-life is 10 seconds. After how many seconds would there no longer be any Polonium isotope left in the container?

A. 30 seconds

B. 60 seconds

C. 70 seconds

D. Impossible to have no polonium left.

2

21

Explanation

The correct answer is C.

With a half-life of 10 seconds there would be 32 molecules after 10 seconds, 16 after 20, 8 after 30, 4 after 40, 2 after 50, 1 after 60 and 0.5 at 70. Candidates may be inclined to select D but they should note it does not contain the term isotope and also that in regard to half life there is a point where to remaining isotope is present, once less than 1 is reached.

Post Comment

Atomic structure

11. Which of the following decay processes has the greatest mass change for a nucleus?

A. Gamma decay

B. Beta decay

C. Neutron emission

D. Alpha decay.

1

0

Explanation

The correct answer is D.

Alpha decay results in the release of He, this will have the greatest impact on nucleus mass.

Post Comment

Atomic structure

12. It takes an unstable isotope 60 years to decrease from 1000kg to 125kg. What is the half life of this isotope?

A. 20 years

B. 60 years

C. 40 years

D. 1 year

1

0

Explanation

The correct answer is A.

Candidates can immediately rule out answer b. We need one half life to reach 500kg, three halflives would bring us to 125kg, therefore the half life is 20 years.

Post Comment

Boiling, melting and freezing points

Below is a bar graph showing the melting and boiling points of various elements.

Image reference: https://www.chemguide.co.uk/atoms/structures/period3.html

13. Considering the graph above what is the unit in which temperature is measured?

A. Celsius

B. Farheinheit

C. Kelvin

D. Thermometry

1

0

Explanation

The correct answer is C.

Candidates should be able to reason that considering the information on the right of the bar graph Kelvin is the unit of temperature used.

Post Comment

Boiling, melting and freezing points

Below is a bar graph showing the melting and boiling points of various elements.

Image reference: https://www.chemguide.co.uk/atoms/structures/period3.html

14. At a temperature of 1000 which is the correct list of elements which will be in a liquid state?

A. Na, Mg, Al, Si

B. Al, Si

C. Si

D. No elements will be in a liquid state.

2

40

Explanation

The correct answer is A.

Candidates should read the graphs carefully and ensure they use the top of each bar as an indicator for when an element reaches it’s melting and boiling point. Remembering this candidates should then read across from 1000 and determine that answer A is correct as when an element is boiling it is transitioning from a liquid to a gas but this does not mean it is only in a gaseous state.

Post Comment

Sam Medicmind Tutor

Tue, 08 Feb 2022 13:26:10

But if look at Si we see it doesn't melt until just over 1500K so how can it be liquid at 1000K?

Isabella Medicmind Tutor

Tue, 02 Aug 2022 14:52:40

I agree Sam. The answer should be only Na, Mg and Al in my opinion

Harriet Medicmind Tutor

Tue, 09 Aug 2022 13:41:41

Could you clarify how Si is liquid at 1000K please?

Ethan Medicmind Tutor

Sun, 19 Mar 2023 04:02:26

FYI, Silicon's melting point is 1683 K

Boiling, melting and freezing points

Below is a bar graph showing the melting and boiling points of various elements.

Image reference: https://www.chemguide.co.uk/atoms/structures/period3.html

15. Which of the following statements best describes the element Ar in regard to its melting and boiling point?

A. The element does not have a melting or boiling point.

B. The element simultaneously reaches its melting and boiling point.

C. The element has only a melting point as it cannot reach a gaseous state.

D. The element has only a boiling point as it is only a liquid.

1

0

Explanation

The correct answer is B.

The two bars on the graph are in line with one another, there is not a way to know if the other options are factual based on the information in the graph.

Post Comment

Boiling, melting and freezing points

Below is a bar graph showing the melting and boiling points of various elements.

Image reference: https://www.chemguide.co.uk/atoms/structures/period3.html

16. At a temperature of 1500 what state would Si be in?

A. Liquid

B. Solid beginning to transition to a liquid.

C. Gaseous

D. Combination of liquid and gaseous.

1

9

Explanation

The correct answer is B.

On the graph at slightly above 1500 the element will have reached its boiling point and is therefore beginning to transition into a liquid state.

Post Comment

JK Medicmind Tutor

Sat, 14 Aug 2021 18:44:36

B.P. --> Liquid state???

Arthur Jones Medicmind Tutor

Sat, 04 Sep 2021 09:54:00

The melting point is clearly above 1500

Alex Medicmind Tutor

Sun, 19 Dec 2021 23:50:13

The melting point means that there will be a phase change from a solid to a liquid. Since the melting point has not been reached yet, it cannot be already in the liquid state. Thus I opted to select 'B' as my answer.

DC Medicmind Tutor

Sun, 26 Dec 2021 10:34:47

Using the same logic as another question, @1500 it isn't necessarily a liquid it's just transitioning. Kind of hard to study when the test can't even be consistant

Sam Medicmind Tutor

Tue, 08 Feb 2022 13:29:49

B should be the correct answer. If it has not yet reached its melting point then it is a solid . It will not transition to a liquid until the melting point is reached. Only then will it begin to transition

Bonds

Image reference: https://www.chemistrylearner.com/chemical-bonds

Look at the diagram above and correctly identify the names for each bond type in the following questions

17. Identify the correct name for A.

A. Ionic bond

B. Covalent bond

C. Metallic bond

D. Hydrogen bond

1

0

Explanation

The correct answer is A.

Post Comment

Bonds

Image reference: https://www.chemistrylearner.com/chemical-bonds

Look at the diagram above and correctly identify the names for each bond type in the following questions

18. Identify the correct name for C.

A. Ionic bond

B. Covalent bond

C. Metallic bond

D. Hydrogen bond

1

0

Explanation

The correct answer is D.

Post Comment

Bonds

Image reference: https://www.chemistrylearner.com/chemical-bonds

Look at the diagram above and correctly identify the names for each bond type in the following questions

19. Identify the correct name for B.

A. Ionic bond

B. Covalent bond

C. Metallic bond

D. Hydrogen bond

0

7

Explanation

The correct answer is C.

Post Comment

Harriet Medicmind Tutor

Tue, 09 Aug 2022 13:44:18

This diagram is very unclear which is A, B, C or D.

sarah Medicmind Tutor

Mon, 08 Jul 2024 03:15:18

agreed with harriet

Bonds

Image reference: https://www.chemistrylearner.com/chemical-bonds

Look at the diagram above and correctly identify the names for each bond type in the following questions

20. Identify the correct name for D.

A. Ionic bond

B. Covalent bond

C. Metallic bond

D. Hydrogen bond

0

6

Explanation

The correct answer is B.

Post Comment

Simran Medicmind Tutor

Tue, 03 Aug 2021 09:16:12

The question says identify D but the letter D is nowhere on the diagram, so how are you suppose to answer this?

Stephanie Medicmind Tutor

Fri, 28 Jan 2022 10:17:34

It's extremely hard to see the diagram and the letters A-D are not in order. So this is essentially a trick question.

21. Which of the following would be an example of an ionic bond?

A. Potassium and chlorine

B. Two atoms of iodine

C. Hydrogen and Helium

D. Argon and helium

1

0

Explanation

The correct answer is A.

Potassium and chlorine would meet the requirements of an ionic bond.

Post Comment

22. A hydrogen bond is a bond between a hydrogen and a what?

A. Electropositive atom

B. Electroneutral atom

C. Electronegative atom

D. Any atom

0

Explanation

The correct answer is C.

Hydrogen bonds form between hydrogen and electronegative atoms.

Post Comment

23. What is the correct definition of a polar and a non-polar covalent bond?

A. In a polar covalent bond, electrons are unequally distributed between the atoms. In a non-polar covalent bond, the electrons are equally shared between the two atoms.

B. In a non-polar covalent bond, electrons are unequally distributed between the atoms. In a polar covalent bond, the electrons are equally shared between the two atoms.

C. There is no difference between polar and non-polar bonds, they both share electrons equally however what dictates if it is polar or non-polar is whether the atoms binding are metal or non-metal.

D. There is no difference between polar and non-polar bonds, they both share electrons unequally however what dictates if it is polar or non-polar is whether the atoms binding are metal or non-metal.

0

Explanation

The correct answer is A.

This is the correct definition for polar and non-polar. Answers C and D are incorrect in information used. Candidates should be able to use the image at the start of the stem to identify what polar and non-polar are.

Post Comment

24. What is the correct equation for the polar molecule borane?

A. 2 boron + 2 hydrogen

B. Boron + 2 hydrogen

C. Boron + 4 hydrogen

D. Boron + 3 hydrogen

1

0

Explanation

The correct answer is D.

Candidates can use the definition of polar and their knowledge of electrons in each hydrogen and boron to solve this question.

Post Comment

25. Which of the following provides the most correct answer for why atoms form chemical bonds?

A. To create new compounds that are more beneficial.

B. Due to attracting electronegative forces.

C. To attain more electrons in their outer shell.

D. To make their outer shell of electrons more stable.

0

Explanation

The correct answer is D.

A and B are not correct. Candidates may be inclined to choose C but should remember that electrons can be gained or lost to benefit and atom.

Post Comment

26. What type of energy is stored in a covalent bond?

A. Kinetic

B. Potential

C. Ionization

D. Mechanical

0

Explanation

The correct answer is B.

The energy present holding atoms together in a molecule is potential energy as it has the possibility to be changed into something else.

Post Comment

Bonds

27. Look at the image above and select the correct bond type for methanol.

A. Ionic

B. Covalent

C. Hydrogen

D. Metallic

0

2

Explanation

The correct answer is C.

There is a hydrogen bond present.

Post Comment

z Medicmind Tutor

Tue, 03 Jan 2023 04:51:07

there is also covalent?

chloe Medicmind Tutor

Wed, 03 Jan 2024 12:25:48

yeah there are also covalent bonds. inaccurate website.

Bonds

28. How many potassium and oxygen atoms would be required to create an ionic bond?

A. 1 potassium 1 oxygen

B. 2 potassium 1 oxygen

C. 1 potassium 2 oxygen

D. 2 potassium 2 oxygen

0

Explanation

The correct answer is B.

Potassium has 1 electron in its outer shell and oxygen has 6 therefore 2 potassium and 1 oxygen are required.

Post Comment

Ethan Medicmind Tutor

Sun, 19 Mar 2023 04:09:12

please tell me they will give us periodic table for this type of question...

jenny Medicmind Tutor

Tue, 04 Jul 2023 11:32:53

im not sure but that seems kinda ridiculous to learn numbers for the entire periodic table

Bonds

29. How many aluminium and bromide molecules would be required to make an ionic bond?

A. 1 aluminium and 3 bromide

B. 2 aluminium and 2 bromide

C. 3 aluminium and 2 bromide

D. 3 aluminium and 3 bromide

0

Explanation

The correct answer is A.

Aluminium has 3 electrons in its outer shell and bromide has 7 therefore you require 3 bromide and 1 aluminium.

Post Comment

Bonds

30. How many magnesium and nitrogen are required to form an ionic bond?

A. 1 magnesium and 4 nitrogen

B. 1 magnesium and 3 nitrogen

C. 2 magnesium and 2 nitrogen

D. 3 magnesium and 2 nitrogen

0

Explanation

The correct answer is D.

Magnesium has 2 electrons in its outer shell and Nitrogen has 5 electrons in its outer shell therefore 3 magnesium and 2 nitrogen are required to form an ionic bond.

Post Comment

Charlotte Medicmind Tutor

Thu, 11 Aug 2022 10:43:06

Sorry, I still don't understand this question!

chloe Medicmind Tutor

Wed, 03 Jan 2024 12:34:16

Mg has 2 electrons in its outershell thus wants to lose those 2 electrons to maintain a stable orbit. N has 5 electrons in its outershell thus wants to gain 3 more to maintain a stable orbit (8 electrons in an outershell is considered stable). the 3 Mg will add up to a total of 6 electrons it wants to lose, whereas the 2 N will add up to a total of 6 electrons it wants to gain. hence it is able to form ionic bonds and fulfill each others needs. or u could do the cross and swap method > Mg2+ and N3-, cross and swap and you will get Mg3N2, which means 3Mg and 2N are required.

Bonds

31. What is the electric charge of ionic compounds?

A. Positive

B. Negative

C. Neutral

D. It is ion dependent

0

Explanation

The correct answer is C.

Ions that are used to create an ionic compound will cancel each other out and thus the compound will have a neutral charge.

Post Comment

Bonds

32. Which of the following statements are correct?

A. Cations are negatively charged. Anions are positively charged.

B. Cations are positively charged. Anions are negatively charged.

C. Cations can be positive or neutral in charge. Anions are negatively charged.

D. Cations are negatively charged. Anions are positively or neutrally charged.

0

Explanation

The correct answer is B.

C and D are not possible, ions are either positive or negative. B should be identified as correct through prior knowledge.

Post Comment

Covalent bonds

33. Which of the following provides the most accurate definition for a covalent bond?

A. A covalent bond forms when two non-metal atoms share a pair of electrons from the outer shell.

B. A covalent bond forms when two metal atoms share a pair of electrons from the outer shell.

C. A covalent bond forms when one metal and one non metal atom share a pair of electrons from the outer shell.

D. A covalent bond forms when any two atoms share a pair of electrons from their inner shell.

1

Explanation

The correct answer is A.

Candidates should have the prior knowledge to answer this question.

Post Comment

Mitch Medicmind Tutor

Fri, 18 Mar 2022 07:13:03

What kind of explanation is this? There's no attempt to explain the reasoning behind why the answer is correct.

Covalent bonds

34. Which of the following statements about the difference between sigma and pi bonds is correct?

A. The maximum number of bonds for each bond type is two.

B. The energy level of the bonds are the same.

C. Sigma bonds use hybridized orbitals to overlap and form a bond.

D. Pi bonds form overlapping hybridised bonds.

0

Explanation

The correct answer is C.

A and B can be ruled out as they do not discuss a difference. Candidates can use prior knowledge to recall that pi bonds form unhybridized bonds therefore D is incorrect.

Post Comment

Stephanie Medicmind Tutor

Fri, 28 Jan 2022 11:41:30

Answer C also do not discuss a difference. Just saying.

Covalent bonds

35. What is the systematic name for the following compound which is commonly known as asparagine?

A. (R)-2-amino-3-carboxylbutanamide

B. (S)-2-amino-4-carbomylbutanoid acid

C. (S)-2-amino-3-carbomylopropanoic acid

D. (R)-3amino-3-carboxylpropanamide

0

8

Explanation

The correct answer is C.

The compound is an acid which eliminates answers a and d. There appear to be 4 carbons but one is an amide therefore the answer needs 3 carbons in it which makes C correct.

Post Comment

Covalent bonds

36. Look at the table above and select which of the following statements is true regarding the data.

A. Both the melting and boiling points decrease as you increase the straight hydrocarbon chain length.

B. Branching of hydrocarbons increases the melting point and decreases the boiling point.

C. Odd numbered hydrocarbons have a higher melting point than the even ones.

D. The more spherically-shaped hydrocarbons have higher melting points than cylindrically shaped ones.

0

8

Explanation

The correct answer is D.

Candidates do not require prior knowledge to answer this question. Looking at the table they should be able to identify the inaccuracies of the first 3 statements.

Post Comment

Stephanie Medicmind Tutor

Fri, 28 Jan 2022 11:46:26

Why is B incorrect, it is a true statement.

Sam Medicmind Tutor

Tue, 08 Feb 2022 13:50:26

B is incorrect because branching also decreases the melting point

Sam Medicmind Tutor

Tue, 08 Feb 2022 13:52:01

My mistake, Steph is right, B is a true statement

Chromatography

Image reference: https://archive.manylabs.org/lesson/80/chromatographyAndPolarity/

37. What is label 1 identifying?

A. Solution

B. Mixture

C. Solvent

D. Solute

0

Explanation

The correct answer is C.

For chromatography to occur a solvent is required, therefore C is correct.

Post Comment

Chromatography

Image reference: https://archive.manylabs.org/lesson/80/chromatographyAndPolarity/

38. Of the labels which corresponds to a mixed substance?

A. 4

B. 3

C. 6

D. 1

0

Explanation

The correct answer is B.

Number 4 indicates the individual pigments that make up the mixture indicated by number 3. 1 cannot be known to be a mixture and 6 refers to the pencil line.

Post Comment

Chromatography

Image reference: https://archive.manylabs.org/lesson/80/chromatographyAndPolarity/

39. Which pigment is the most polar?

A. Red

B. Yellow

C. Blue

D. Green

0

4

Explanation

The correct answer is D.

See explanation below.

In paper chromatography polarity is the factor responsible for separating a mixture into its components. The more polar components of a mixture do not dissolve in a substance, meaning they are the pigments that do not travel as far up the paper.

Post Comment

Chromatography

Image reference: https://archive.manylabs.org/lesson/80/chromatographyAndPolarity/

40. Which pigment is the least polar?

A. Red

B. Yellow

C. Blue

D. Green

0

1

Explanation

The correct answer is A.

In paper chromatography polarity is the factor responsible for separating a mixture into its components. The more polar components of a mixture do not dissolve in a substance, meaning they are the pigments that do not travel as far up the paper.

Post Comment

Energy diagram question

41. Look at the following diagram and determine which of the following statements is incorrect.

A. Bond enthalpy: ΔH₃

B. Heat of formation: ΔH₅

C. Heat of sublimation: ΔH₁

D. Ionisation energy: ΔH₂

0

2

Explanation

The correct answer is B.

CsF is in a solid state coming from gaseous products therefore it is not as the result of heat formation meaning B is incorrect.

Post Comment

jenny Medicmind Tutor

Tue, 04 Jul 2023 11:37:38

the explanation doesnt make sense - it says that b is incorrect ??

KiKi Medicmind Tutor

Fri, 18 Aug 2023 13:50:02

So is B correct or not?

Enzymes.

42. Consider the reaction shown and select what the most appropriate type of catalytic strategy is being shown?

A. Electrochemical catalysis

B. Covalent catalysis

C. Hydrogen catalysis

D. Acid/base catalysis

0

Explanation

The correct answer is D.

Post Comment

Mitch Medicmind Tutor

Fri, 18 Mar 2022 07:15:47

Explanation???

Harriet Medicmind Tutor

Tue, 09 Aug 2022 14:09:54

Could you explain the reasoning?

Nethanya Medicmind Tutor

Wed, 04 Dec 2024 16:38:18

Since the reaction simply moves the hydrogen from the hydroxyl group to the alpha carbon, this is an acid/base catalysis. This is because it involves rearranging of protons on a single molecule like in a keto-enol tautomerism. (I am not sure whether this explaination is sufficient)

Enzymes.

43. Which of the following is true regarding this equation?

A. This is a reversible reaction.

B. This is an irreversible reaction.

C. This is an incomplete reaction.

D. This is a partial reaction.

1

3

Explanation

The correct answer is A.

Post Comment

Sam Medicmind Tutor

Wed, 09 Feb 2022 11:41:30

Where is the equation???

Karthig Medicmind Tutor

Wed, 24 Aug 2022 15:19:39

It is referring to the equation in the previous question.

Enzymes.

44. Potassium cyanide binds with cytochrome a₃ to prevent oxygen binding to the enzyme. When this occurs the Km of the reaction is not altered. What type of inhibition is this?

A. Competitive inhibition

B. Non-competitive inhibition

C. Reversible inhibition

D. Partial inhibition

1

0

Explanation

The correct answer is B.

As the Km of the reaction is not altered therefore it is not competitive inhibition.

Post Comment

Enzymes.

45. What is the effect of enzymes on activation energy?

A. Increase activation energy of the reaction.

B. Stabilise the activation energy of the reaction.

C. Lower the activation energy of the reaction.

D. Use up the activation energy of the reaction.

1

0

Explanation

The correct answer is C.

Enzymes lower activation energy making it easier for a reaction to occur.

Post Comment

Hypochlorous acid dissociates in water to hydronium ions and hypochlorite ions.

HOCl + H₂O <-> H3O⁺ + OCl¯

46. If I add more hypochlorite ions to the solution what will the impact on hypochlorous acid be?

A. It depends on the number of ions added.

B. Increase

C. Decrease

D. Remain the same.

1

0

Explanation

The correct answer is B.

Addition of hypochlorite ions shifts the point of equilibria and forms for hypochlorous acid.

Post Comment

Hypochlorous acid dissociates in water to hydronium ions and hypochlorite ions.

HOCl + H₂O <-> H3O⁺ + OCl¯

47. What would the addition of more H20 to the solution be?

A. Increased hydronium, increased hypochlorite, decreased hypochlorous acid.

B. Increased hydronium, increased hypochlorite, increased hypochlorous acid.

C. Decreased hydronium, decreased hypochlorite, increased hypochlorous acid.

D. Decreased hydronium, increased hypochlorite, decreased hypochlorous acid.

0

Explanation

The correct answer is A.

Candidates should use the equation at the top to answer this question.

Post Comment

Hypochlorous acid dissociates in water to hydronium ions and hypochlorite ions.

HOCl + H₂O <-> H3O⁺ + OCl¯

48. If you were informed that hypochlorous acid is measured to have Kb = 3.2 x 10-¹⁸ what would this mean?

A. Weak acid

B. Weak base

C. Strong acid

D. Strong base

0

7

Explanation

The correct answer is C.

This Kb measure indicates the substance to be a strong acid.

Post Comment

Mitch Medicmind Tutor

Fri, 18 Mar 2022 07:17:31

Isn't a strong acid the same as a weak base?

jenny Medicmind Tutor

Tue, 04 Jul 2023 11:39:48

why would b be incorrect - Kb is the base dissociation constant

chloe Medicmind Tutor

Wed, 03 Jan 2024 12:42:22

a strong acid has a weak conjugate base. given that HOCl is a strong acid, its conjugate base, OCl-, will be a weak base.

Hypochlorous acid dissociates in water to hydronium ions and hypochlorite ions.

HOCl + H₂O <-> H3O⁺ + OCl¯

49. A solution has a hydronium ion concentration of 10⁴ M. What is it’s pH?

A. 4

B. 8

C. -4

D. -8

0

3

Explanation

The correct answer is C.

pH is the inverse of the log therefore it is -4.

Post Comment

Isabella Medicmind Tutor

Tue, 02 Aug 2022 14:59:20

Isn't the pH scale from 0 to 14? So how can you have a negative pH value?

Jocelyn Medicmind Tutor

Fri, 19 Aug 2022 08:30:29

I agree with Isabella, can you please explain why is the answer -4?

chloe Medicmind Tutor

Wed, 03 Jan 2024 12:45:21

a negative pH is possible as long as there is a high H+ concentration. pH of the solution is calculated by -log(100000) = -4

Felix Medicmind Tutor

Mon, 20 Jan 2025 02:16:13

how is this -4 it doesn't make sense ph is positive value

50. In an equilibrated, stochiometric mixture of ammonia (NH₃) and hydrochloric acid (HCl), what would the pH be?

A. 7

B. >7

C. <7

D. ~7

0

Explanation

The correct answer is C.

As ammonia is a weak base the solution remains slightly acid.

Post Comment

51. To achieve a completely neutral pH what would need to happen to the ammonia and hydrochloric acid mixture?

A. Add more hydrochloric acid

B. Add more ammonia

C. Add bicarbonate solution

D. Add nitric acid

1

2

Explanation

The correct answer is B.

Adding more of the weak base will enable a neutral pH to be reached.

Post Comment

52. Which of the following would have the weakest conjugate?

A. Weak acid

B. Strong acid

C. Weak base

D. Strong base

0

5

Explanation

The correct answer is D.

Strong bases ionise almost irreversibly therefore their products are weak conjugate acids.

Post Comment

Mitch Medicmind Tutor

Fri, 18 Mar 2022 07:19:01

Strong acids also have weak conjugate bases????

KiKi Medicmind Tutor

Fri, 18 Aug 2023 14:02:07

Agree with Mitch, the question doesn't specify which conjugate to choose. You can immediately rule out A and C, however D is not technically the only correct answer.

Rate law

53. Look at the reaction below and select what the appropriate answer for its overall order of reaction.

A. 0

B. 1

C. 2

D. 3

0

Explanation

The correct answer is B.

The overall order for a reaction is the sum of the individual reaction orders.

Post Comment

Rate law

R=k[C₆H₅N₂Cl]² [H₂O]¹

54. Where the R of the equation to read as above what would the overall order of reaction be?

A. 0

B. 1

C. 2

D. 3

0

Explanation

The correct answer is D.

The overall order for a reaction is the sum of the individual reaction orders.

Post Comment

Rate law

55. Which of the following statements regarding rate law is correct?

A. The overall rate law is determined by the fastest step of a reaction.

B. The presence of a catalyst will increase the number of molecules moving out of a transition state.

C. The overall rate law is determined by the slowest step of a reaction.

D. The presence of a catalyst will prevent molecules from entering a transition state.

0

Explanation

The correct answer is C.

Candidates should know what a catalyst is and be able to identify that answers B and D are not correct options. Candidates should be able to reason that the slowest aspect of a reaction will dictate its overall rate not the fastest aspect of it.

Post Comment

Rate law

56. Which of the following statements regarding rate law is correct?

A. Increasing temperature will increase the rate of a reaction.

B. Decreasing temperature will decrease the rate of a reaction.

C. Increasing the amount of zero order reactants available will increase the rate of product yield.

D. Removing a catalyst will result in an increased number of molecules existing in a transition state.

1

2

Explanation

The correct answer is A.

Candidates should be able to identify that of the statements either A or B are going to be correct and that a temperature increase will accelerate the rate of a reaction.

Post Comment

Stephanie Medicmind Tutor

Fri, 28 Jan 2022 23:06:16

How can you have a multiple choice question that only allows one answer and have more than one be correct?!

Ethan Medicmind Tutor

Sun, 19 Mar 2023 04:18:22

the explanation is obviously wrong, T has proportional relation with reaction rate, so B is wrong. The only scenario where decrease T would "positively" affects a reaction is during an endothermic reaction, but what been affected in that case is equilibrium constant but not reaction rate.

Hybridisation

57. What is the orbital arrangement of the element boron?

A. 1s²2s²2p¹

B. 2s²1s²2p¹

C. 1s²1s²2p¹

D. 1s²2s²1p¹

0

Explanation

The correct answer is A.

Consider the number of electrons present for boron and how the s and p shells fill.

Post Comment

Hybridisation

58. Boron trifluoride, BF₃, has a trigonal planar shape formed by 3 B-F bonds. There are no lone pairs. What is the hybridisation around the boron atom in BF₃?

A. sp

B. sp²

C. sp³

D. s, p

0

Explanation

The correct answer is B.

Main group elements has one s and 3 p orbitals in their valence shell that can be involved in bonding. The shape of the molecule is what identifies how these orbitals mix together, in this case it is a trigonal planar shape. This means that there will be an s and 2 p orbitals used.

Post Comment

Ethan Medicmind Tutor

Sun, 19 Mar 2023 04:20:50

one simple trick to solve this kind of question is by counting number of lone pair electron and sigma bond. In this case 0 lone pair, 3 single bond, add them up and match with the hybridisation with same power sum (S1P2)

Hybridisation

59. BeF₂ has a linear shape. What is the hybridisation around the beryllium atom?

A. sp

B. sp²

C. sp³

D. s, p

0

Explanation

The correct answer is A.

Linear shapes have central atoms with 2 sets of bonds and no lone pairs therefore there are two hybrid orbitals.

Post Comment

Hybridisation

60. Carbon tetrachloride, CCl₄ has a tetrahedral shape formed by four C-Cl bonds. What is the hybridisation around the carbon atom?

A. sp

B. sp²

C. sp³

D. s, p

0

Explanation

The correct answer is C.

Consider the shape which requires an s orbital and 3 p orbitals to form it.

Post Comment

Lewis dot structures

61. What would be the correct written equation for the diagram above?

A. PO₃

B. PO₃²¯

C. PO₃¯

D. PO₃³¯

1

Explanation

The correct answer is D.

Post Comment

Mitch Medicmind Tutor

Fri, 18 Mar 2022 07:21:09

Explanation???

Jocelyn Medicmind Tutor

Fri, 19 Aug 2022 08:42:59

Is this answer accurate?

Will Medicmind Tutor

Mon, 25 Mar 2024 15:24:34

this answer is correct

Lewis dot structures

62. What is the charge of the above lewis dot structure?

A. -2

B. 0

C. -1

D. 1

0

Explanation

The correct answer is A.

Post Comment

Isabella Medicmind Tutor

Tue, 02 Aug 2022 15:01:56

What is the explanation?

Ethan Medicmind Tutor

Sun, 19 Mar 2023 04:25:40

A simple formula to solve this question is Number electron in outer shell of presents form - Number electron presents in diagram = charge. In this case 24 - 26 = -2 (any line counts as 2 electron in diagram)

Lewis dot structures

63. How many electrons are required to make a complete outer ring for Oxygen?

A. 8

B. 6

C. 7

D. 9

0

Explanation

The correct answer is A.

Post Comment

Isabella Medicmind Tutor

Tue, 02 Aug 2022 15:02:09

What is the explanation?

Lewis dot structures

64. What is the charge of the above Lewis dot structure?

A. -1

B. -2

C. 0

D. 1

0

1

Explanation

The correct answer is B.

Post Comment

Isabella Medicmind Tutor

Tue, 02 Aug 2022 15:02:22

What is the explanation?

Liquids

65. What does the buoyant force on an object floating on a liquid most directly depend on?

A. Liquid viscosity

B. Liquid mass

C. Object volume

D. Liquid density

2

0

Explanation

The correct answer is D.

The more dense a liquid the longer it would take an object to sink through it.

Post Comment

Steph Medicmind Tutor

Sat, 09 Sep 2023 23:04:23

i thought buoyant force was determined by volume of liquid and density of object??

Liquids

66. Considering Newton’s third law for answering this question. A 8kg block is suspended from a scale, the block is then lowered into 500ml of water contained in a 1litre container until it floats. How will the weight registered on the scale change?

A. Increase

B. Decrease

C. Stay the same

D. Become zero

0

9

Explanation

The correct answer is A.

The third law states there are equal and opposite forces acting against each other to keep an object in equilibrium therefore the scale will register a higher mass.

Post Comment

Ethan Medicmind Tutor

Sun, 19 Mar 2023 04:28:31

The explanation makes no sense, I consider "suspend" means to hang the block and lowered to water, wouldnt the buoyant force cancels the gravitational force?

KiKi Medicmind Tutor

Fri, 18 Aug 2023 14:21:50

I read the question the same way Ethan did, can someone explain?

Liquids

67. Which of the following most accurately represents Pascal’s law?

A. Pressing a brake with a 10N force over a small area of the break pad for a short distance of time to stop a car.

B. The volume displaced in a hydraulic lift by piston 1 is equal to that of piston 2.

C. Pressing down a stopper on a jug of water with a 20N force will see the same force exerted on the bottom of the jug.

D. Dropping a bag of IV fluid made of thick plastic will see the force of the drop equally distributed throughout the bag thus preventing it from breaking open.

0

3

Explanation

The correct answer is B.

Pascal’s law states that pressure is transmitted undiminished to every portion of fluid and wall of a container therefore the forces of the pistons must be equal.

Post Comment

Stephanie Medicmind Tutor

Fri, 28 Jan 2022 23:26:27

If, as you say, "Pascal’s law states that pressure is transmitted undiminished to every portion of fluid and wall of a container therefore the forces of the pistons must be equal.", then how is B correct when it talks about volume, while C, which is what I chose, talks about force, which in liquids, is pressure?!

Will Medicmind Tutor

Mon, 25 Mar 2024 15:28:58

Use process of elimination here, A and C are incorrect and D doesn't refer to pascals law

Liquids

A 30kg block is dropped into acetic acid which has a specific gravity of 1.06. Once in the acid the block weighs 240N. Use this information to answer the following questions.

68. What is the initial weight in N of the block?

A. 240N

B. 3000N

C. 30N

D. 300N

1

Explanation

The correct answer is D.

Post Comment

Lois Medicmind Tutor

Mon, 22 Aug 2022 19:42:38

how do we do this calculation?

Mig Medicmind Tutor

Fri, 03 Mar 2023 15:25:44

They basically just rounded grvaity (9.81) to 10, force/mass = gravity and just rearrange

Ethan Medicmind Tutor

Sun, 19 Mar 2023 04:30:42

Why would they put a physics question in chemistry section??

Brian Forde Medicmind Tutor

Sat, 04 Jan 2025 00:52:17

More of a physics question i would have thought.

Liquids

A 30kg block is dropped into acetic acid which has a specific gravity of 1.06. Once in the acid the block weighs 240N. Use this information to answer the following questions.

69. What is the kg change in the weight of the block once it is submerged in the acetic acid?

A. 2kg

B. 3kg

C. 6kg

D. 12kg

0

1

Explanation

The correct answer is C.

Post Comment

Liquids

A 30kg block is dropped into acetic acid which has a specific gravity of 1.06. Once in the acid the block weighs 240N. Use this information to answer the following questions.

70. What is the buoyant force present?

A. 80N

B. 100N

C. 60N

D. 240N

0

1

Explanation

The correct answer is C.

Post Comment

Mitch Medicmind Tutor

Fri, 18 Mar 2022 07:24:24

Explanation??

jenny Medicmind Tutor

Tue, 04 Jul 2023 11:47:45

can anyone explain this ?

KiKi Medicmind Tutor

Fri, 18 Aug 2023 14:27:31

How I explained it to myself : The box weighed 300N, once in the acid it weighed 240N. So 300N - 240N = 60N. Making the answer C.

Liquids

A 30kg block is dropped into acetic acid which has a specific gravity of 1.06. Once in the acid the block weighs 240N. Use this information to answer the following questions.

71. What is another term for specific gravity?

A. Relative density

B. Weight

C. Mass

D. Exertional force

0

Explanation

The correct answer is A.

Post Comment

Liquids

A 30kg block is dropped into acetic acid which has a specific gravity of 1.06. Once in the acid the block weighs 240N. Use this information to answer the following questions.

72. How does the specific gravity of the block compare to that of acetic acid?

A. Cannot be measured

B. Lower

C. Equal

D. Higher

0

1

Explanation

The correct answer is D.

Post Comment

jenny Medicmind Tutor

Tue, 04 Jul 2023 11:48:17

explanation?

Larry Medicmind Tutor

Thu, 16 May 2024 05:45:26

I think if specific gravity is defined as the ratio of the block's density over the acetic acid's density, since the value is more than 1, then the density of the block has to be higher than the acetic acid

Liquids

A 30kg block is dropped into acetic acid which has a specific gravity of 1.06. Once in the acid the block weighs 240N. Use this information to answer the following questions.

73. If a 50kg block were submerged instead how would the specific gravity change?

A. Increase

B. Decrease

C. Stay the same

D. Cannot be known

0

1

Explanation

The correct answer is A.

Post Comment

Larry Medicmind Tutor

Thu, 16 May 2024 05:41:38

There was no explanation here, but it increases because the heavier block would mean it is denser than the previous block and therefore it has a proportionately higher density to acetic acid. Right?

Brian Forde Medicmind Tutor

Sat, 04 Jan 2025 01:04:17

Crazy question. Specific Gravity is a property of the fluid, it should not be changed by the addition of a solid block. Spec Grav usually references to water as the comparison

Chemistry - Part 1 Review Screen

Instructions

Below is a summary of your answers. You can review your questions in three (3) different ways.

The buttons in the lower right-hand corner correspond to these choices:

1. Review all of your questions and answers.
2. Review questions that are incomplete.
3. Review questions that are flagged for review. (Click the 'flag' icon to change the flag for review status.)

You may also click on a question number to link directly to its location in the exam.

Your Time has Finished

Loading...

GAMSAT Section III Chemistry – Part 1

Your Score: %

Average Score of All Users:

Section Breakdown

Chemistry - Part 1

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation

Explanation