Question

Lead nitrate can be decomposed by heating. What is the percent yield of the decomposition reaction if 9.9 g of `Pb(NO_3)_2`are heated to give 5.5 g of `PbO`??

Answer 1

`"Percentage yield"~=80%`

Explanation:

We need (i) a stoichiometric equation........

`Pb(NO_3)_2 +Delta rarr PbO(s)+2NO_2(g)+1/2O_2(g)`

This simply must be known; nitrates undergo thermal decomposition to give oxide and nitric oxide and dioxygen gas.

And (ii). given the 1:1 stoichiometry between nitrate and oxide, we needs equivalent quantities of lead oxide and lead nitrate:

`"Percentage yield"="Moles of lead oxide"/"Moles of lead nitrate"xx100%=`

`((5.5*g)/(223.2*g*mol^-1))/((9.9*g)/(331.2*g*mol^-1))xx100%=??%`