How many moles of oxygen atoms are present in 0.150 mol of calcium nitrate, Ca(NO3)2?
Show the answer and explanation
Correct answer
D. 0.900 mol
Principle or equation
The formula Ca(NO3)2 contains 2 nitrate ions, each with 3 oxygen atoms, so 6 oxygen atoms per formula unit. Moles of O atoms = moles of compound × 6.
Why this answer is correct
0.150 mol × 6 = 0.900 mol of oxygen atoms.
Example
For 0.200 mol of Mg(NO3)2, oxygen moles = 0.200 × 6 = 1.200 mol.
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