According to the balanced chemical equation: \rm K_2SO_(3\,(aq)) + 2HNO_(3\,(aq)) \rightarrow 2KNO_(3\,(aq)) +SO_(2\,(g)) + H_2O_(\,(l)) when 100.0 mL of 0.100 M \rm K_2SO_(3\,(…

Question

According to the balanced chemical equation:


`\rm K_2SO_(3\,(aq)) + 2HNO_(3\,(aq)) \rightarrow 2KNO_(3\,(aq)) +SO_(2\,(g)) + H_2O_(\,(l))`

when 100.0 mL of 0.100 M
`\rm K_2SO_(3\,(aq))` is mixed with 100.0 mL of 0.200 M
`\rm HNO_(3\,(aq))` at 30°C and 1 atm, the volume of
`\rm SO_2` gas produced is 0.24 L. Assuming the reacting goes to completion, which of the following changes would double the volume of
`\rm SO_(2\,(g))` produced at the same temperature and pressure? For each change, assume that the other solutions and volumes remain the same.


A) Using 200.0 mL of the 0.100 M
`\rm K_2SO_(3\,(aq))` because then it becomes the reactant in excess

B) Using 200.0 mL of the 0.200 M
`\rm HNO_(3\,(aq))` because the volume of
`\rm SO_(2\,(g))` produced is inversely proportional to the number of moles at constant temperature and pressure

C) Using 200.0 mL of 0.100 M
`\rm K_2SO_(3\,(aq))` and 200.0 mL of 0.200 M
`\rm HNO_(3\,(aq))` because this provides double the number of moles with the correct stoichiometric ratio

D) Using 400.0 mL of 0.100 M
`\rm K_2SO_(3\,(aq))` and 200.0 mL of 0.200 M
`\rm HNO_(3\,(aq))` because this provides the same number of moles of each reactant

Answer 1

C) Using 200.0 mL of 0.100 M K₂SO₃ and 200.0 mL of 0.200 M HNO₃ because this provides double the number of moles with the correct stoichiometric ratio.

Step-by-step explanation:

Given the balanced chemical equation ...

K₂SO₃ +2HNO₃ ⇒ 2KNO₃ +SO₂ +H₂O

with 0.01 moles of K₂SO₃ and 0.02 moles of HNO₃ reacting completely to produce 0.24 L of SO₂ gas, you want to know the change required to double the amount of gas produced.

Limiting reactants

The given reactants are supplied in the 1 : 2 stoichiometric ratio required for using the reactants completely. Hence doubling the output of the reaction requires doubling the amount of both inputs. This is described by choice C:

C) Using 200.0 mL of 0.100 M K₂SO₃ and 200.0 mL of 0.200 M HNO₃ because this provides double the number of moles with the correct stoichiometric ratio.