What is the amount of drug in grams contained in 250ml of a 7% solution?

To determine the amount of drug in grams contained in 250 ml of a 7% solution, you can use the definition of a percentage concentration. A 7% solution means there are 7 grams of drug in every 100 ml of solution.

First, find out how many 100 ml units are in 250 ml. You can do this by dividing 250 ml by 100 ml:

250 ml ÷ 100 ml = 2.5

Next, since each 100 ml contains 7 grams of the drug, you can calculate the total amount of drug in 250 ml by multiplying the number of 100 ml units (2.5) by the grams of drug in each unit (7 grams):

2.5 × 7 grams = 17.5 grams

Thus, the amount of drug in 250 ml of a 7% solution is 17.5 grams, making this the correct answer.