Final answer:
The percentage of chlorine in the compound C4H8SCl2 is calculated by determining the total mass of chlorine and dividing it by the compound's molar mass. The result is approximately 44.66%, which rounds to choice C. 45%.
Step-by-step explanation:
To determine the percentage of chlorine in the compound C4H8SCl2, we need to calculate the total mass of chlorine in the compound and then divide this by the molar mass of the compound. Chlorine has two isotopes, Cl-35 and Cl-37, but for this calculation, we need only the combined mass of all chlorine atoms in the compound. Each chlorine atom contributes to the molar mass based on its atomic mass, which is approximately 35.5 amu (when accounting for the natural abundance of both isotopes).
Since there are two chlorine atoms in the compound, the total mass of chlorine is:
2 x 35.5 amu = 71 amu
Now we divide the total chlorine mass by the molar mass of the entire compound:
(71 amu / 159.09 g/mol) x 100% = 44.66%
The closest answer to this calculated value would be C. 45%.