question $1$: iron$($III$)$ oxide reacts with carbon monoxide according to the equation:

$F{e}_2{O}_3(s)+3CO(g)2Fe(s)+3C{O}_2(g)$

A reaction mixture initially contains $20\mathrm{.}15gF{e}_2{O}_3$ and $17\mathrm{.}68$gCO.

Part A

Once the reaction has occurred as completely as possible, what mass $($in grams$)$ of the excess reactant is left?

Express your answer in grams to three significant figures.

question $2$:

Magnesium oxide can be made by heating magnesium metal in the presence of oxygen. The balanced equation for the reaction is

$2Mg(s)+O_2(g)2$MgO$(s)$

When $13\mathrm{.}7g$ of $Mg$ is allowed to react with $16\mathrm{.}3g{O}_2,14\mathrm{.}5$gMgO is collected.

Part A

Determine the theoretical yield for the reaction.

Express your answer in grams to three significant figures.

Part b

Determine the peltent yield for the reaction.

Express the percentage to three significant figures.