Find the concentration of solution in terms of weight percent if 20g of common salt is dissolved in 70g of water..

Explanation

To find the concentration of a solution in terms of weight percent, we can follow these steps:

### Step 1: Identify the mass of solute and solvent
- The mass of common salt (solute) is given as 20 grams.
- The mass of water (solvent) is given as 70 grams.

### Step 2: Calculate the total mass of the solution
- The total mass of the solution is the sum of the mass of the solute and the mass of the solvent.

\[ \text{Total mass of solution} = \text{mass of solute} + \text{mass of solvent} = 20 \, \text{g} + 70 \, \text{g} = 90 \, \text{g} \]

### Step 3: Use the formula for weight percent concentration
- The weight percent concentration is calculated using the formula:

\[ \text{Weight percent} = \left( \frac{\text{mass of solute}}{\text{mass of solution}} \right) \times 100 \]

### Step 4: Substitute the values into the formula
- Substitute the mass of the solute (20 g) and the total mass of the solution (90 g) into the formula:

\[ \text{Weight percent} = \left( \frac{20 \, \text{g}}{90 \, \text{g}} \right) \times 100 \]

### Step 5: Calculate the weight percent
- Perform the calculation:

\[ \text{Weight percent} = \left( \frac{20}{90} \right) \times 100 \approx 22.22\% \]

### Final Answer
- The concentration of the solution in terms of weight percent is approximately **22.22%**.

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