21 Best Revision Questions in Chemistry

Question 1 (Multiple Choice Worth 2 points)

[07.06]<object:standard:sc.912.p.8.10>In the chemical reaction shown below, which element was reduced?

Zn + H₂SO₄  ZnSO₃+ H₂O

Zn, because it gained 2 electrons

Zn, because it lost 2 electrons

S, because it gained 2 electrons

S, because it lost 2 electrons

 

 

Question 2 (Multiple Choice Worth 2 points)

[05.03]<object:standard:sc.912.p.12.10>If 1.6 moles of an ideal gas are at a temperature of 25°C and a pressure of 0.91 atm Hg, what volume would the gas occupy, in liters?

0.28 L

3.0 L

36 L

43 L

 

 

Question 3 (Multiple Choice Worth 2 points)

[05.01]<object:standard:sc.912.p.8.1>Which phase of matter is made up of particles that are packed relatively close together, with an indefinite shape but a definite volume?

gas

liquid

plasma

solid

 

 

Question 4 (Multiple Choice Worth 2 points)

[06.04]<object:standard:sc.912.p.10.2>Which of the following circumstances will result in a reaction that is spontaneous only at low temperatures?

positive enthalpy change and positive entropy change

negative enthalpy change and negative entropy change

positive enthalpy change and negative entropy change

negative enthalpy change and positive entropy change

 

 

Question 5 (Multiple Choice Worth 2 points)

[08.03]<object:standard:sc.912. l.17.19=””>Which of the following best describes the forces that create natural gas?

Heat from the Earth’s core and pressure transform the remains of dead plants and animals.

Energy of the sun strikes photovoltaic cells producing a flow of electrons.

Heat energy beneath the Earth’s surface heats underground water into steam.

Heat energy is released during nuclear fission and steam is produced to turn a turbine.

 

 

Question 6 (Multiple Choice Worth 2 points)

[07.06]<object:standard:sc.912.p.8.8>Which of the following chemical reactions is an oxidation-reduction reaction?

Fe₂O₃ + 3CO  2Fe + 3CO₂

MgSO₄ + 2KI K₂SO₄ + MgI₂

NaNO₃ + KCl  KNO₃ + NaCl

Cu(NO₃)₂ + 2HBr CuBr₂ + 2HNO₃

 

 

Question 7 (Multiple Choice Worth 2 points)

[08.01]<object:standard:sc.912.p.10.11, sc.912.p.10.12=””>Which of the following represents a balanced nuclear equation showing Bismuth-212 undergoing alpha decay followed by beta decay?

+   x- +

+   +   x-

+    +

+    +

 

 

Question 8 (Multiple Choice Worth 2 points)

[07.03]<object:standard:sc.912.p.8.11> What is the concentration of hydronium ions in a solution with a pH = 3.9?

4.14 × 10^-2

7.80 × 10^-3

1.26 × 10^-4

3.00 × 10^-5

 

 

Question 9 (Multiple Choice Worth 2 points)

[07.02]<object:standard:sc.912.p.8.8, sc.912.p.8.11=””>Which of the following is the salt in the Brønsted-Lowry neutralization reaction?

HBr + NaHCO₃  H₂CO₃ + NaBr

HBr

NaHCO₃

H₂CO₃

NaBr

 

 

Question 10 (Multiple Choice Worth 2 points)

[05.07]<object:standard:sc.912. p.8.9.=””>How many grams of potassium nitrate (KNO₃) would form if 2.25 liters of a 1.50 molar lead nitrate Pb(NO₃)₂ solution reacts with 1.15 liters of a 2.75 molar potassium chromate K₂CrO₄solution?

Pb(NO₃)₂ + K₂CrO₄  PbCrO₄ + 2KNO₃

108 g

681 g

639 g

362 g

 

 

Question 11 (Multiple Choice Worth 2 points)

[06.04]<object:standard:sc.912.p.10.6>On a potential energy diagram for the following processes, which of the following has a decrease in entropy?

ice melts

water freezes

water boils

sublimation of dry ice into carbon dioxide gas

 

 

Question 12 (Multiple Choice Worth 2 points)

[07.02]<object:standard:sc.912.p.8.8, sc.912.p.8.11=””>If it requires 37.5 mL of a 0. 245 M HBr solution to neutralize 18.0 mL Mg(OH)₂, what is the concentration of the Mg(OH) ₂ solution?

2 HBr + Mg(OH) ₂  Mg(Br) ₂ + 2 H₂O

0.0120 M

0.0255 M

0.118 M

0.510 M

 

 

Question 13 (Multiple Choice Worth 2 points)

[08.04]<object:standard:sc.912.n.4.2>What is the purpose of environmental remediation?

to restore water to its original purity levels

to make the most of currently used technologies and resources

to remove pollution or contamination from the environment

to reuse materials that would otherwise go to waste

 

 

Question 14 (Multiple Choice Worth 2 points)

[06.05]<object:standard:sc.912.n.3.5, sc.912.p.12.12=””>According to the collision theory and model created to explain the collision theory, why does a catalyst cause a reaction to speed up?

It lowers the activation energy.

It increases the collisions per minute.

It increases the average kinetic energy of the particles.

It increases the kinetic energy and the collisions per minute.

 

 

Question 15 (Multiple Choice Worth 2 points)

[07.04]<object:standard:sc.912.p.12.13>What is the correct balanced equation for the following equilibrium constant expression?

CO_{2 (g)}  CO _(g) + ½ O_{2 (g)}

CO_{2 (g)}  CO _(g) + O_{2 (g)}

2 CO_{2 (g)}  2 CO _(g) + O_{2 (g)}

2CO _(g) + O_{2 (g)}  CO_{2 (g)}

 

 

Question 16 (Multiple Choice Worth 2 points)

[08.03]<object:standard:sc.912. l.17.19=””>Which of the following natural resources is considered renewable?

biofuel

natural gas

nuclear power

oil

 

 

Question 17 (Multiple Choice Worth 2 points)

[06.05]<object:standard:sc.912.n.3.5, sc.912.p.12.12=””>According to the collision theory and model created to explain the collision theory, what two factors must be satisfied for a given collision to be successful and result in the production of products?

Correct molecular shape and momentum.

Correct position and maximum potential.

Correct density and threshold velocity.

Correct orientation and sufficient energy.

 

 

Question 18 (Multiple Choice Worth 2 points)

[08.02]<object:standard:sc.912.p.10.11> Which describes nuclear power plants?

They generate power directly from nuclear reactions.

They supply over 50% of the nation’s power needs.

Compared to fossil fuels, they require much less fuel.

They have more atmospheric pollutants compared to fossil fuels.

 

 

Question 19 (Multiple Choice Worth 2 points)

[06.02]<object:standard:sc.912.p.10.7>When sulfuric acid is poured on sugar the volume expands, it turns black and gets very hot. Which of the following best describes this reaction?

endothermic

exothermic

decomposition

synthesis

 

 

Question 20 (Multiple Choice Worth 2 points)

[05.08]<object:standard:sc.912.p.8.2.>Which of the following solutions will have the greatest colligative effect?

2 moles of glucose (C₆H₁₂O₆) dissolved in 1.0 kg of water (H₂O)

1.5 moles of sodium chloride (NaCl) dissolved in 1000.0 kg of water (H₂O)

0.75 moles of calcium fluoride (CaF₂) dissolved in 500.0 g of water (H₂O)

0.50 moles of carbon dioxide (CO₂) dissolved in 250.0 g of water (H₂O)

 

 

Question 21 (Multiple Choice Worth 2 points)

[08.06]<object:standard:sc.912. l.16.10=””>Biotechnology has allowed us to genetically modify corn with a gene that acts as a pesticide. What could be a possible environmental impact of this development?

Insects resistant to the specific pesticide would develop over time.

The surplus of corn would rot and decay releasing additional greenhouse gases.

The price of corn would drop dramatically because of a greater supply with no increase in demand.

Countries able to buy the new corn seeds would see increases in their economy and pollution would rise.

 

 

Question 22 (Multiple Choice Worth 2 points)

[05.01]<object:standard:sc.912.p.8.1, sc.912.p.8.2=””>Which of the following describes what occurs as a liquid becomes a solid?

A physical change occurs; the particles of the liquid vibrate faster and their kinetic energy increases.

A physical change occurs; the particles of the liquid vibrate more slowly and their kinetic energy decreases.

A chemical change occurs; the particles of the liquid vibrate faster and their kinetic energy increases.

A chemical change occurs; the particles of the liquid vibrate more slowly and their kinetic energy decreases.

 

 

Question 23 (Multiple Choice Worth 2 points)

[05.06]<object:standard:sc.912.l.18.12>In a body of water, the surface tension caused by the attraction between water molecules is strong. Which of the following is a consequence of this property?

Water is considered to be a universal solvent.

When water freezes, the molecules move farther apart.

Only a limited amount of solute can be dissolved in a sample of water.

Objects with a higher density than water can be observed floating on water.

 

 

Question 24 (Multiple Choice Worth 2 points)

[07.05]<object:standard:sc.912.p.12.13>What would happen to the following endothermic reaction that is in equilibrium if heat is added?

N₂O_{4 (g)}  2 NO_{2 (g)}

The reaction would not be affected

The equilibrium would shift to the left

The equilibrium would shift to the right

The product concentration would equal the reactants

 

 

Question 25 (Multiple Choice Worth 2 points)

[05.03]<object:standard:sc.912.p.12.10>A sample of gas has a volume of 2.4 L and a pressure of 1.2 atm. What would the pressure of the same gas sample be if the volume is reduced to 1.8 L at a constant temperature?

0.90 atm

1.6 atm

5.2 atm

3.6 atm

 

 

Question 26 (Multiple Choice Worth 2 points)

[07.03]<object:standard:sc.912.p.8.11>Which is not true regarding the pH scale?

The neutral pH at 25°C is 7.0.

Bases have a pH greater than 7.0.

The pH scale measures the hydronium ion concentration in solution.

When the concentration of hydroxide ions increases, the pH decreases.

 

 

Question 27 (Multiple Choice Worth 2 points)

[06.04]<object:standard:sc.912.p.10.2>Which of the following reactions results in a decrease in entropy?

CaCO_{3 (s)}  CaO _(s) + CO_{2 (g)}

N₂O₄ (g)  2NO_{2 (g)}

CaO _(s) + SO_{3 (g)}  CaSO_{4 (s)}

2NH_{3 (g)}  N_{2 (g)} + 3H_{2 (g)}

 

 

Question 28 (Multiple Choice Worth 2 points)

[07.06]<object:standard:sc.912.p.8.10>What is the oxidation number of sulfur (S) in sulfuric acid (H₂SO₄)?

-6

+2

+4

+6

 

 

Question 29 (Multiple Choice Worth 2 points)

[06.04]<object:standard:sc.912.p.10.6>For an exothermic reaction, which of the following conditions must be true for all products?

The change in enthalpy is positive and potential energy diagram is higher.

The change in enthalpy is negative and potential energy diagram is higher.

The change in enthalpy is positive and potential energy diagram is lower.

The change in enthalpy is negative and potential energy diagram is lower.

 

 

Question 30 (Multiple Choice Worth 2 points)

[05.04]<object:standard:sc.912.p.12.10, sc.912.p.8.9=””>When 7.50 L of sulfur trioxide are produced by the reaction of sulfur dioxide in an excess of oxygen at standard temperature and pressure, how many liters of sulfur dioxide were used?

2SO_{2 (g)} + O_{2 (g)}  2SO_{3 (g)}

3.75 L

5.00 L

7.50 L

15.0 L

 

 

Question 31 (Multiple Choice Worth 2 points)

[06.01]<object:standard:sc.912.p.10.2>If you drop a 150 gram piece of metal that has a temperature of 125°Celsius into 1000 grams of water at 20°Celsius, what best describes what would occur?

More heat will be lost by the metal than gained by the water.

The temperature of the water will be greater than the amount of heat lost by the metal.

The temperature change of the metal will equal the temperature change of the water.

The heat lost by the metal will equal the heat gained by the water.

 

 

Question 32 (Multiple Choice Worth 2 points)

[06.03]<object:standard:sc.912.p.10.5>Which is not true regarding the specific heat of water?

The specific heat of water explains capillary action.

The specific heat of water is 4.18 J/(°C × g).

Water is useful as an engine coolant because of its high specific heat

The specific heat of water is the reason islands have milder climates.

 

 

Question 33 (Multiple Choice Worth 2 points)

[05.05]Which of the following would be the best technique to use in order to separate a liquid from a solution?

chromatography

evaporation

filtration

simple distillation

 

 

Question 34 (Multiple Choice Worth 2 points)

[08.01]<object:standard:sc.912.p.10.11, sc.912.p.10.12=””>Which statement is not correct regarding radiation?

Nuclear reactions arise from an atom’s nucleus.

Alpha, Beta, and Gamma are types of radiation.

Most of the earth’s nuclear energy comes from the Sun.

Radioactive elements have an unbalanced number of protons and electrons.

 

 

Question 35 (Multiple Choice Worth 2 points)

[08.05]<object:standard:sc.912.p.8.12>Carbon naturally occurs in two forms: diamond and graphite. Why do these two forms have very different properties?

The key difference is that diamonds have other elements bonded within their structure.

The differences are explained by the number of covalent and ionic bonds within each substance.

The differences are explained by the density: graphite is very high and diamond is much lower.

The differences are explained by how the carbon atoms within each substance are covalently bonded together.

 

 

Question 36 (Multiple Choice Worth 2 points)

[05.06]When 5.6 grams of NaCl are dissolved in enough water to create a 125-gram solution, what is the solution’s concentration, expressed as a percent by mass?

3.6% NaCl

3.8% NaCl

4.5% NaCl

4.7% NaCl

 

 

Question 37 (Multiple Choice Worth 2 points)

[06.02]<object:standard:sc.912.p.10.6>On an endothermic potential energy diagram, what is true for all products?

The products are at the same energy level as the reactants.

The products are at a lower energy level than the reactants.

The products are at a higher energy level than the reactants.

The products do not have energy.

 

 

Question 38 (Multiple Choice Worth 2 points)

[06.03]<object:standard:sc.912.p.10.2, sc.912.p.10.5=””>125.0 g of an unknown substance is heated to 97.0°C. It is then placed in a calorimeter than contains 250g of water with an initial temperature of 20.0°C. The final temperature reached by the calorimeter is 23.5°C. What is the specific heat of the unknown substance? The specific heat of water is 4.18 J/ (°C × g).

0.285 J/ (°C × g)

0.398 J/ (°C × g)

0.729 J/ (°C × g)

1.24 J/ (°C × g)

 

 

Question 39 (Multiple Choice Worth 2 points)

[06.01]<object:standard:sc.912.p.10.2>How would a system which exchanges energy but does not exchange matter between the system and the surroundings be classified?

an open system

an isolated system

a closed system

an integrated system

 

 

Question 40 (Multiple Choice Worth 2 points)

[07.05]<object:standard:sc.912.p.12.13>Which of the following is not a result when a change to an equilibrium system is applied?

Increasing the rate of the forward reaction will cause a shift to the left.

Increasing the rate of the reverse reaction will cause a shift to the left.

Decreasing the rate of the forward reaction will cause a shift to the left.

Decreasing the rate of the reverse reaction will cause a shift to the right.

 

 

Question 41 (Multiple Choice Worth 2 points)

[08.04]<object:standard:sc.912.l.17.15>Which of the following best summarizes the main causes of water pollution today?

increased runoff, driving, discarded oil

evaporation, new construction, overpopulation

waste from wildlife, decaying vegetation, automobiles

leaking septic and sewer systems, manufacturing, farming

 

 

Question 42 (Multiple Choice Worth 2 points)

[08.05]<object:standard:sc.912.p.8.12>A carbon atom has a strong tendency to do which of the following?

double bond with electrons

receive electrons

donate electrons

share electrons

 

 

Question 43 (Multiple Choice Worth 2 points)

[07.01]<object:standard:sc.912.p.8.11>What is the difference between a strong acid and a weak acid?

A strong acid has a higher pH than a weak acid.

A strong acid is 100% ionized, a weak acid is less than 100% ionized.

A strong acid is diprotic or triprotic, a weak acid is monoprotic.

A strong acid has a greater concentration of hydroxide ions compared to a weak acid.

 

 

Question 44 (Multiple Choice Worth 2 points)

[07.01]<object:standard:sc.912.p.8.11>Which of the following is not true of acids?

Acids are corrosive.

Dilute acids feel slippery.

Acids have a distinctly sour taste.

Acids have more hydronium ions than hydroxide ions

 

 

Question 45 (Multiple Choice Worth 2 points)

[07.04]<object:standard:sc.912.p.12.13>Which answer does not describe the following reaction?

NO _(g) + O_{2 (g)}  2 NO_{2 (g)}

The reaction is in dynamic equilibrium.

The reaction does not go to completion.

The reaction is reversible.

The concentration of reactants and products will be equal.

 

 

Question 46 (Multiple Choice Worth 2 points)

[08.02]<object:standard:sc.912.p.10.11>How can a sample of uranium-235 that has critical mass be induced to react?

It must be spilt with a laser.

It must be fused to a helium nucleus.

It must be bombarded it with neutrons.

It must be shot with light speed electrons.