Question

a 5.775 - gram sample of iron is heated in the presence of excess chlorine. a metal chloride is formed with a mass of 16.77 g. determine the empirical formula of the metal chloride. enter the elements in the order fe, cl. empirical formula =

Explanation:

Step1: Calculate moles of iron

The molar mass of iron (Fe) is approximately 55.85 g/mol. Moles of Fe = $\frac{\text{mass of Fe}}{\text{molar - mass of Fe}}=\frac{5.775\ g}{55.85\ g/mol}\approx0.1034\ mol$.

Step2: Calculate mass of chlorine

The mass of the metal - chloride is 16.77 g. Mass of Cl = mass of metal - chloride - mass of Fe = 16.77 g - 5.775 g = 10.995 g.

Step3: Calculate moles of chlorine

The molar mass of chlorine (Cl) is approximately 35.45 g/mol. Moles of Cl = $\frac{\text{mass of Cl}}{\text{molar - mass of Cl}}=\frac{10.995\ g}{35.45\ g/mol}\approx0.3101\ mol$.

Step4: Find the ratio of moles

Divide the number of moles of each element by the smaller number of moles. For Fe: $\frac{0.1034\ mol}{0.1034\ mol}=1$. For Cl: $\frac{0.3101\ mol}{0.1034\ mol}\approx3$.

Answer:

FeCl₃