Concept:The mass of 1 mole of any compound is simply its molar mass, calculated by summing the individual atomic masses of every atom present in its chemical formula.
Formula:$$ M = \sum \text{Atomic Masses} $$
Solution:- The chemical formula is \( \text{CaCO}_3 \).
- Identify standard atomic masses from the periodic table:
- Calcium (Ca) = 40 g/mol
- Carbon (C) = 12 g/mol
- Oxygen (O) = 16 g/mol (And there are 3 of them)
- Add them together: \( 40 + 12 + (3 \times 16) \).
- \( 40 + 12 + 48 = 100 \text{ g/mol} \).
- Therefore, 1 mole weighs exactly 100g.
Why other options are incorrect:- 50g, 70g, 125g: These represent incorrect atomic summations, such as forgetting to multiply oxygen by 3, or using the atomic number of Calcium (20) instead of its atomic mass (40).
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