Final answer:
To determine the empirical formula of a compound of zinc and chlorine, convert the masses to moles, find the simplest whole number ratio, and match to the formula ZnCl2.
Step-by-step explanation:
To determine the empirical formula for a compound composed of zinc and chlorine, we first need to calculate the moles of each element in the compound. The molar mass of zinc (Zn) is approximately 65.38 g/mol and the molar mass of chlorine (Cl) is approximately 35.45 g/mol. Using these molar masses, we can convert the given masses of the elements to moles:
- Moles of zinc: 47.9 g Zn × (1 mol Zn / 65.38 g Zn) = 0.7325 moles Zn
- Moles of chlorine: 52.1 g Cl × (1 mol Cl / 35.45 g Cl) = 1.470 moles Cl
We then divide the moles of each element by the smallest number of moles to get the ratio of atoms:
- Zinc to chlorine ratio: 0.7325 moles Zn / 0.7325 = 1 Zn; 1.470 moles Cl / 0.7325 = 2 Cl
This results in a Zn to Cl ratio of 1:2, which corresponds to the empirical formula ZnCl2. Thus, the correct option is B) ZnCl2.