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2 years ago

Can yall help me with this one, thanks!

Chemistry

1 answer:

Lynna [10]2 years ago

5 0

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 = $\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{23}{40}\times 100=57.5\%$

O : number of atom= 1

Molar mass= 16 g/mol

Total mass of NaOH = 40 g/mol

% composition by mass = $\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{16}{40}\times 100=40\%$

H : number of atom= 1

Molar mass= 1 g/mol

Total mass of NaOH = 40 g/mol

% composition by mass = $\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{1}{40}\times 100=2.5\%$

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