Calculate the mass percent of oxygen in chromium(iii) carbonate. round your answer to the nearest percentage.

The percentage is 50.7%

Explanation:

The formula of chromium (III) carbonate is (Cr₂(CO₃)₃)

Let us calculate the molar mass of (Cr₂(CO₃)₃)

molar mass of (Cr₂(CO₃)₃) =

2X atomic mass of Cr + 3X atomic mass of C + 9X atomic mass of O

molar mass of (Cr₂(CO₃)₃) = 2X 52 + 3X12 +9X16 = 284g/mol

As per the formula there are nine moles of oxygen in each mole of (Cr₂(CO₃)₃).

so we can say that

In 284g of (Cr₂(CO₃)₃) the mass of oxygen = 144g

so 1 g of (Cr₂(CO₃)₃) the mass of oxygen =

Therefore

the mass of oxygen in 100g of(Cr₂(CO₃)₃) =0.507X100=50.7

Thus percentage of Oxygen in (Cr₂(CO₃)₃) =50.7%

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.