Question

a 18.72 g sample of copper is heated in the presence of excess chlorine. a metal chloride is formed with a mass of 29.16 g. determine the empirical formula of the metal chloride. use the references to access important values if needed for this question. 3 item attempts remaining try another version submit answer

Explanation:

Step1: Calculate mass of chlorine

The mass of chlorine in the metal - chloride is the mass of the metal - chloride minus the mass of copper. So, $m_{Cl}=29.16\ g - 18.72\ g=10.44\ g$.

Step2: Calculate moles of copper and chlorine

The molar mass of copper ($Cu$) is $M_{Cu}=63.55\ g/mol$, and the molar mass of chlorine ($Cl$) is $M_{Cl}=35.45\ g/mol$.
The moles of copper, $n_{Cu}=\frac{m_{Cu}}{M_{Cu}}=\frac{18.72\ g}{63.55\ g/mol}\approx0.2946\ mol$.
The moles of chlorine, $n_{Cl}=\frac{m_{Cl}}{M_{Cl}}=\frac{10.44\ g}{35.45\ g/mol}\approx0.2945\ mol$.

Step3: Find the ratio of moles

Divide both number of moles by the smaller number of moles (in this case, they are approximately equal). The ratio of $n_{Cu}:n_{Cl}\approx1:1$.

Answer:

$CuCl$