Question 4 of 28beginner🔧 ApplyNumerical3 marks

A common talcum powder contains 4 % m/m zinc oxide, which acts as an antiseptic. How much zinc oxide is present in 300 g of the talcum powder?

Correct Answer

12 g

Exercise: Pause and Ponder | Q: 1 | (Page 5)
For More Understanding

Explanation

The mass by mass percentage (% m/m) indicates the grams of solute present in 100 grams of the total solution. Given that the talcum powder contains 4% m/m zinc oxide, it means 4 g of zinc oxide is present in 100 g of talcum powder. Using the formula, Mass by mass percentage = (Mass of solute / Mass of solution) × 100, we can substitute the given values to find the mass of the solute (zinc oxide) in 300 g of the talcum powder.

Solution Steps

  1. Given: Mass of talcum powder (solution) = 300 g, Mass by mass percentage (% m/m) of zinc oxide = 4%

  2. Formula: Mass by mass percentage = (Mass of solute / Mass of solution) × 100

  3. Substitution: 4 = (Mass of zinc oxide / 300 g) × 100

  4. Calculation: Mass of zinc oxide = (4×3004 \times 300 g) / 100 = 12 g

PreviousNext