What is the percent composition of ca(oh)2? 37.7% ca, 53.0% o, and 10.3% h 45.5% ca, 38.2% o, and 16.3% h 54.0% ca, 43.0% o, and 2.7% h 64.7% ca, 27.0% o, and 8.3% h

The molar mass of Calcium hydroxide is 74 g/mol

To find the percent composition we have to find the number of atoms of each element in the formula .

So there’s

Calcium - 1

Oxygen - 2

Hydrogen - 2

Then have to multiply the relative atomic mass of each element by the number of atoms

Ca - 40 g/mol x 1 = 40

O - 16 g/mol x 2 = 32

H - 1 g/mol x 2 = 2

Then To find percent composition of each element we have to divide the mass of each element in the formula by the relative molecular mass of calcium hydroxide

Ca - 40 / 74 x 100 % = 54.0%

O - 32 / 74 x 100 % = 43.2 %

H - 2 / 74 x 100 % = 2.7%

From the options given correct answer is 3rd option

54.0% Ca , 43.0% O and 2.7 % H

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons