Question

question 7 10 pts 4.7 g of metallic zinc reacts with copper(ii) chloride producing metallic copper and zinc chloride. what is the expected mass of metallic copper produced in this reaction? the equation for the reaction is zn + cucl₂ → cu + zncl₂ 4.6 g 4.7 g 4.8 g 3.0 g

Explanation:

Step1: Determine molar masses

The molar mass of $Zn$ is $M_{Zn}=65.38\ g/mol$, and the molar mass of $Cu$ is $M_{Cu} = 63.55\ g/mol$.

Step2: Calculate moles of Zn

The number of moles of $Zn$, $n_{Zn}=\frac{m_{Zn}}{M_{Zn}}$, where $m_{Zn} = 4.7\ g$. So $n_{Zn}=\frac{4.7\ g}{65.38\ g/mol}\approx0.072\ mol$.

Step3: Use stoichiometry

From the balanced chemical equation $Zn + CuCl_{2}\to Cu+ZnCl_{2}$, the mole - ratio of $Zn$ to $Cu$ is $1:1$. So the number of moles of $Cu$ produced, $n_{Cu}=n_{Zn}= 0.072\ mol$.

Step4: Calculate mass of Cu

The mass of $Cu$, $m_{Cu}=n_{Cu}\times M_{Cu}$. Substituting $n_{Cu}=0.072\ mol$ and $M_{Cu}=63.55\ g/mol$, we get $m_{Cu}=0.072\ mol\times63.55\ g/mol\approx4.6\ g$.

Answer:

4.6 g