Can yall help me with this one, thanks!

Answer:
Element atom molar mass Total % composition
Na 1 23 40 57.5 %
O 1 16 40 40%
H 1 1 40 2.5 %
The given compound is NaOH.
Na : number of atom= 1
Molar mass= 23 g/mol
Total mass of NaOH = 40 g/mol
% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{23}{40}\times 100=57.5\%[/tex]
O : number of atom= 1
Molar mass= 16 g/mol
Total mass of NaOH = 40 g/mol
% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{16}{40}\times 100=40\%[/tex]
H : number of atom= 1
Molar mass= 1 g/mol
Total mass of NaOH = 40 g/mol
% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{1}{40}\times 100=2.5\%[/tex]