Question

his is the chemical formula for chromium(III) nitrate: . Calculate the mass percent of oxygen in chromium(III) nitrate. Round your answer to the nearest percentage.

Answer 1

Answer:

$\%\ Composition\ of\ iron=69.92\ \%$

Explanation:

Percent composition is percentage by the mass of element present in the compound.

The formula for chromium(III) nitrate is $Cr(NO_3)_3$

Molar mass of chromium(III) nitrate = 238.011 g/mol

1 mole of chromium(III) nitrate contains 9 moles of oxygen

Molar mass of oxygen = 16 g/mol

So, Mass= Molar mass*Moles = 16*9 g = 144 g

$\%\ Composition\ of\ iron=\frac{Mass_{iron}}{Total\ mass}\times 100$

$\%\ Composition\ of\ iron=\frac{144}{238.011}\times 100$

$\%\ Composition\ of\ iron=69.92\ \%$