Question

2 Cu + 1 O₂ 2 CuOWhat mass of copper is used to produce 2.87 moles of copper (II) oxide?

Answer 1

To solve this problem we need to calculate the molar mas of Cu and CuO:

`\begin{gathered} Mm_(Cu)=63.546\text{ g/mol} \\ Mm_(CuO)=79.545\text{ g/mol} \end{gathered}`

because of the chemical equation we know that 2 mols of Cu produce 2 mols of CuO. Now we have to convert those mols into mass, to do that we multiply the number of mols by the molar mass already calculated:

`m_(CuO)=n_(CuO)\cdot Mm_(CuO)=2mol\cdot79.545g/mol=159.09g`

this means that for 2 mols of Cu that are consumed 159.09 g of CuO are produced. Then we just need to use this information to calculate the right proportion for 2.87mols of Cu. we can do that using a conversion factor:

`2.87\text{ mols of Cu}\cdot\frac{159.09\text{ g of CuO}}{2mols\text{ of Cu}}=228.294g\text{ of CuO}`

228.294 g of CuO are produced