Which of following solution is most concentrated?

Options

A. 4% NaOH aq.
B. 4% NaOH solution, `d_("solution")=1.1`(gm/ml)
C. 4 grams of NaOH dissolved in 80 ml solution
D. all of these solutions are equally concentrated

Explanation

To determine which of the given solutions is the most concentrated, we will calculate the molarity for each solution. Molarity (M) is defined as the number of moles of solute per liter of solution.

### Step-by-Step Solution:

1. **Calculate Molarity of 4% Aqueous NaOH:**
- **Given:** 4% NaOH means 4 grams of NaOH in 100 grams of water.
- **Molecular Weight of NaOH:**
- Sodium (Na) = 23 g/mol
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