Concept:Converting macroscopic mass into moles requires establishing the mass in grams and dividing it by the molar mass of the compound. Ice is chemically identical to liquid water (\( \text{H}_2\text{O} \)).
Formula:$$ n = \frac{\text{mass (g)}}{\text{molar mass}} $$
Solution:- Convert 1 kg into grams: \( 1 \text{ kg} = 1000 \text{ grams} \).
- The molar mass of water (\( \text{H}_2\text{O} \)) = \( (2 \times 1) + 16 = 18 \text{ g/mol} \).
- Divide the mass by molar mass: \( n = 1000 \text{ g} / 18 \text{ g/mol} \).
- \( n = 55.55 \text{ moles} \).
- This is often approximated to \( 55.5 \text{ moles} \).
Why other options are incorrect:- 50 moles: Results from an erroneous calculation (1000 / 20).
- 1000 moles: Assumes a 1:1 ratio between grams and moles, completely ignoring molar mass.
- 100 moles: Results from dividing by 10 instead of 18.
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