Concept:Ice is simply water in a solid state; its chemical formula is still \( \text{H}_2\text{O} \). We must convert the given mass to moles, and then multiply by Avogadro's number to find the molecular count.
Formula:$$ \text{Molecules} = \left( \frac{m}{M} \right) \times N_A $$
Solution:- Molar mass of \( \text{H}_2\text{O} \) = \( (2 \times 1) + 16 = 18 \text{ g/mol} \).
- Moles of ice = \( 10 \text{ g} / 18 \text{ g/mol} \approx 0.555 \text{ moles} \).
- Multiply by Avogadro's constant: \( 0.555 \times 6.022 \times 10^{23} \).
- \( 0.555 \times 6 = 3.33 \). With the decimals, it rounds precisely to \( 3.34 \times 10^{23} \text{ molecules} \).
Why other options are incorrect:- \( 0.34 \times 10^{23} \) & \( 33.1 \times 10^{23} \): Both represent gross decimal point misplacements during the multiplication phase.
- 10: This is the mass in grams, not the microscopic count of molecules.
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