Question

question 5 (3 points)
you are asked to make 125 grams of a 7% antifungal cream using tolnaftate powder and eucerin cream. how many grams of tolnaftate powder are needed? round to the nearest hundredths (w/w).

Explanation:

To determine the amount of tolnaftate powder needed to make 125 grams of a 7% (w/w) antifungal cream, we use the formula for weight - by - weight percentage:

The formula for weight - by - weight percentage is \(\% (w/w)=\frac{\text{mass of solute}}{\text{mass of solution}}\times100\)

Let \(x\) be the mass of tolnaftate powder (the solute). The mass of the solution (the antifungal cream) is 125 grams and the percentage \(\% (w/w) = 7\).

We can re - arrange the formula to solve for \(x\):

$$x=\frac{\% (w/w)\times\text{mass of solution}}{100}$$

Substitute \(\% (w/w)=7\) and \(\text{mass of solution} = 125\space g\) into the formula:

$$x=\frac{7\times125}{100}=\frac{875}{100} = 8.75\space g$$

So, 8.75 grams of tolnaftate powder are needed.

Answer:

To determine the amount of tolnaftate powder needed to make 125 grams of a 7% (w/w) antifungal cream, we use the formula for weight - by - weight percentage:

The formula for weight - by - weight percentage is \(\% (w/w)=\frac{\text{mass of solute}}{\text{mass of solution}}\times100\)

Let \(x\) be the mass of tolnaftate powder (the solute). The mass of the solution (the antifungal cream) is 125 grams and the percentage \(\% (w/w) = 7\).

We can re - arrange the formula to solve for \(x\):

$$x=\frac{\% (w/w)\times\text{mass of solution}}{100}$$

Substitute \(\% (w/w)=7\) and \(\text{mass of solution} = 125\space g\) into the formula:

$$x=\frac{7\times125}{100}=\frac{875}{100} = 8.75\space g$$

So, 8.75 grams of tolnaftate powder are needed.