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alisha [4.7K]
3 years ago
15

Can yall help me with this one, thanks!

Chemistry
1 answer:
Lynna [10]3 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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