Yield And Percentage Yield

Question

In a reaction where 4 g of hydrogen gas reacts with excess chlorine to form HCl, the actual yield obtained is 128 g. What is the percentage yield of HCl? (Molar masses: H$_2$ = 2 g/mol, HCl = 36.5 g/mol)

RankGuru · Accepted Answer

Percentage yield is the ratio of actual yield to theoretical yield, expressed as a percentage. The balanced equation is $\text{H}_2 + \text{Cl}_2 \rightarrow 2\text{HCl}$. Moles of $\text{H}_2 = 4/2 = 2$ mol. From stoichiometry, 1 mol $\text{H}_2$ gives 2 mol HCl, so 2 mol $\text{H}_2$ gives 4 mol HCl. Theoretical mass of HCl $= 4 \times 36.5 = 146$ g. Percentage yield $= (128/146) \times 100 = 87.7\%$. Option 75.2% would imply an actual yield of about 109.8 g, which does not match. Option 80.0% would require a theoretical yield of 160 g — that would mean over 4 mol HCl from 2 mol $\text{H}_2$, violating stoichiometry. Option 95.4% would require a theoretical yield of about 134.2 g, inconsistent with the calculation. This question applies the NCERT concept of theoretical and percentage yield in quantitative analysis. Plausibility check: $128/146 = 0.877$, so percentage yield $= 87.7\%$, and since $128 < 146$, the yield is less than 100%, as expected in a real reaction.

Yield And Percentage Yield

Select the correct option:

🔒 Solution Hidden from View

More some basic concepts in chemistry Practice Questions

Upon complete combustion of 0.45 g of an organic compound containing only C, H, and O, 0.66 g of (...

In the balanced equation for the reaction of aluminium with dilute sulfuric acid to produce aluminiu...

100 mL of 0.5 M (\text{BaCl}_2) solution is mixed with 200 mL of 0.3 M (\text{Na}_2\text{SO}_4) ...

A sample of drinking water was found to contain 0.032 g of fluoride ions dissolved in 16 kg of water...

Consider the reaction: (\text{Fe}_2\text{O}_3 + 3\text{CO} \rightarrow 2\text{Fe} + 3\text{CO}_2)....

A 250 mL solution contains 4.9 g of sulfuric acid ((\text{H}_2\text{SO}_4)). What is the normality...

In the combustion reaction (\text{C}_3\text{H}_8 + 5\text{O}_2 \rightarrow 3\text{CO}_2 + 4\text{H}...

The average atomic mass of chlorine is 35.5 u. Given that chlorine exists as (^{35}\text{Cl}) (ato...

A hydrocarbon contains 92.3% carbon by mass and has a molar mass of 78 g/mol. What is its molecular ...

What mass of sodium hydroxide (NaOH) must be dissolved in 500 mL of water to prepare a 0.4 M solutio...

A solution is prepared by dissolving 18 g of glucose ((\text{C}6\text{H}{12}\text{O}_6), molar m...

A compound is formed by elements A and B such that two atoms of A combine with three atoms of B. If ...

About This Question

Solution