Question

Calculate the formula unit masses of $ZnO,N{a}_{2}O,K_{2}C{O}_3$.
(atomic masses of $Zn=65u,Na=23u,K=39u,C=12u$ and $O=16u$)

Answer 1

Formula unit mass of $ZnO$=(Atomic mass of $Zn$)+(Atomic mass of $O$)

=$(65+16)u$ =$81u$

Formula unit mass of $N{a}_{2}O$=$(2\times 23)+16$

=$62u$

Formula unit mass of $K_{2}C{O}_3$=$(2\times 39)+12+(3\times 16)$

=$138u$