Q: If the reaction $$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3 is $$carried out and produces 5 moles of AB3, what is the percent yield if the theoretical yield is 6 moles?

$$\frac{5}{6} \times 100 = 83.3\%$$

Question 1

Which of the following best describes the chemical reaction illustrated in the second and third images, where molecules with two orange atoms and one black atom react to form molecules with three orange atoms and one black atom?

Accepted Answer

A combination reaction where two reactants form a more complex product.

Question 2

Given the reaction illustrated in the images, if 6 molecules of AB2 react with 3 molecules of B2, what is the balanced chemical equation for the reaction?

Accepted Answer

$$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3$$

Question 3

If the reaction shown in the images is carried out with 8.5 moles of B2 and 4.0 moles of AB2, how many moles of AB3 will be produced?

Accepted Answer

4.0 mol

Question 4

In the context of stoichiometry, what is the limiting reagent in the reaction $$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3 if $$you start with 12 moles of AB2 and 6 moles of B2?

Accepted Answer

Neither, both are present in stoichiometric amounts.

Question 5

If the reaction $$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3 is $$carried out and produces 5 moles of AB3, what is the percent yield if the theoretical yield is 6 moles?

Accepted Answer

$$\frac{5}{6} 	imes 100 = 83.3\%$$

Question 6

If the reaction shown in the images is exothermic, which of the following statements is true about the energy profile of the reaction?

Accepted Answer

The products have lower energy than the reactants.

Question 7

If the reaction $$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3 is $$carried out in a closed container, what will happen to the pressure inside the container as the reaction proceeds, assuming all reactants and products are gases?

Accepted Answer

The pressure will remain constant.

Question 8

If the reaction $$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3 is $$carried out at constant temperature and volume, which law can be used to relate the change in the number of gas molecules to the change in pressure?

Accepted Answer

Avogadro's Law

Question 9

If the reaction $$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3 is $$carried out and the total number of gas molecules before and after the reaction is the same, what does this imply about the entropy change?

Accepted Answer

Entropy remains unchanged.

Question 10

If the reaction $$6\mathrm{AB}_2 + 3\mathrm{B}_2 \rightarrow 6\mathrm{AB}_3 is $$carried out and the reaction is reversible, what will happen at equilibrium?

Accepted Answer

Both reactants and products will be present.

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