Concept:Molarity is a measure of the concentration of a chemical species, specifically defined as the number of moles of solute per liter (or \( \text{dm}^3 \)) of solution.
Formula:$$ \text{Molarity (M)} = \frac{\text{Mass of solute}}{\text{Molar mass of solute}} \times \frac{1000}{\text{Volume in cm}^3} $$
Solution:- Solute (Glucose) mass = \( 10.0 \text{ g} \).
- Molar mass of Glucose (\( \text{C}_6\text{H}_{12}\text{O}_6 \)) = \( 180 \text{ g/mol} \).
- Volume of solution = \( 100 \text{ cm}^3 \).
- Substitute values into the formula: \( M = \left(\frac{10}{180}\right) \times \left(\frac{1000}{100}\right) \).
- \( M = \left(\frac{1}{18}\right) \times 10 = \frac{10}{18} \).
- \( \frac{10}{18} = \frac{5}{9} \approx 0.55 \text{ M} \).
Why other options are incorrect:- 10: Calculates mass per volume without considering the molar mass of glucose.
- 0.1 & 1: Standard distractors based on incorrect conversions from \( \text{cm}^3 \) to \( \text{dm}^3 \).
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