Calculate the mass percent composition of O in each compound. a. calcium nitrate
b. Iron(II) sulfate
c. Carbon dioxide

A. Mass percent composition of oxygen = 58.5%

B. Mass percentage composition of oxygen = 42.1%

C. Mass percentage composition of oxygen = 72.7 %

Explanation:

Percentage mass composition of an element in a compound is given by the formula below:

Percentage mass composition = mass of element/ molar mass of compound × 100%

Percentage mass of oxygen in the given compounds are then calculated.

a. Calcium nitrate, Ca(NO₃)₂: molar mass of compound is obtained first.

Molar mass of Ca(NO₃)₂ = 40 + 14 × 2 + 16 × 2 × 3 = 164 g

Mass of oxygen = 16 × 6 = 96 g

Mass percent composition of oxygen = 96/164 × 100% = 58.5%

b. Iron (ii) sulfate, FeSO₄: molar mass of compound is obtained first.

Molar mass of FeSO₄ = 56 + 32 + 16 × 4 = 152 g

Mass of oxygen = 16 × 4 = 64 g

Mass percentage composition of oxygen = 64/152 × 100% = 42.1%

c. Carbon dioxide, CO₂: molar mass of compound is obtained first.

Molar mass of CO₂ = 12 + 16 × 2 = 44 g

Mass of oxygen = 16 × 2 = 32 g

Mass percentage composition of oxygen = 32/44 × 100% = 72.7 %

indium, and thallium have three electrons i think

it's filtration, but this is an assumption so my apologies if i got this