Final answer:
To calculate the purity percentage of acetic acid, compare the actual mass of carbon in the sample to the expected mass in a pure sample. In this case, the purity percentage is 80.2%, which is not listed among the options provided.
Step-by-step explanation:
To calculate the purity percentage of acetic acid based on content of carbon, we should know that pure acetic acid has a known percentage composition by mass of its elements: carbon (39.9%), hydrogen (6.7%) and oxygen (53.4%). In 125 g of crude acetic acid, if there are 40 grams of carbon, we can find the purity by comparing the actual mass of carbon to the expected mass in pure acetic acid. The calculation is as follows:
Purity percentage = (Actual mass of carbon in sample / Expected mass of carbon in pure sample) × 100
For pure acetic acid, carbon would have a mass of 39.9% of the total mass. So, for 125 g:
Expected mass of C in pure acetic acid = 39.9% of 125 g = 0.399 × 125 g = 49.875 g
Thus:
Purity percentage = (40 g / 49.875 g) × 100 = 80.2%
Therefore, none of the given options A) 25%, B) 32%, C) 40%, D) 60% are correct. The purity percentage of the acetic acid sample is 80.2%.