What is the gram formula mass of calcium carbonate, CaCO₃? (Ca = 40, C = 12, O = 16)
Answer and explanation
Correct answer: B. 100
- Step 1: Add the atomic masses: 40 + 12 + (3 × 16).
- Step 2: 40 + 12 + 48 = 100.
Answer
100.
Why not the others: 68: the three oxygen atoms were counted as one. 84: two oxygen atoms were counted. 116: four oxygen atoms were counted.
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