Question

How many moles of PbS areequivalent to 458 g PbS?(Pb = 207.2 g/mol, S = 32.06 g/mol)=-[?] mol

Answer 1

The first thing we need to do is calculate the molar mass of PbS. They give us the atomic weights of lead (P) and sulfur (S), the molecular weight will be equal to the sum of the atomic weights multiplied by the atoms of each element, as follows:

`\text{Molar mass PbS}=207.2(g)/(mol)*1+32.06(g)/(mol)*1=239.3(g)/(mol)`

Now, to calculate the number of moles we use its molecular mass and apply the following equation:

`\begin{gathered} \text{MolPbS}=GivengPbS*(1molPbS)/(MolarMass,gPbS) \\ \text{MolPbS}=458gPbS*(1molPbS)/(239.3gPbS)=1.9molPbS \end{gathered}`

In 458g of PbS there are 1.9 mol PbS