What is the percent (w/v) for 100 g NaCl dissolved in 250 mL of solution?

What is the percent (w/v) for 100 g NaCl dissolved in 250 mL of solution?

• A. 40%
• B. 20%
• C. 10%
• D. 25%

Answer: (A)

Percent weight/volume shows how many grams of solute are present per 100 milliliters of solution. Here, 100 g of NaCl are dissolved in 250 mL of solution. Use the formula: % w/v = (grams of solute / milliliters of solution) × 100. So (100 g / 250 mL) × 100 = 0.4 × 100 = 40%. This is the correct percent w/v. Remember, this measure uses grams per milliliter (then scaled to per 100 mL), not mass percent or volume percent.

Percent weight/volume shows how many grams of solute are present per 100 milliliters of solution. Here, 100 g of NaCl are dissolved in 250 mL of solution. Use the formula: % w/v = (grams of solute / milliliters of solution) × 100. So (100 g / 250 mL) × 100 = 0.4 × 100 = 40%. This is the correct percent w/v. Remember, this measure uses grams per milliliter (then scaled to per 100 mL), not mass percent or volume percent.