Question

What percent of a drug is contained in a mixture of powder consisting of 0.5 kg, containing 0.038% of a drug, and 10 kg, containing 0.043% of a drug?

Answer 1

The percentage of the drug in the mixture is 0.043%.

Step-by-step explanation:

0.5 kg contains 0.038% of a drug.

Mass of the drug = 0.038% of 0.5

=
`(0.038)/(100)` × 0.5

= 0.00019

= 1.9 ×
`10^(-4)`

10 kg contains 0.043% of the same drug.

Mass of the drug = 0.043% of 10

=
`(0.043)/(100)` × 10

= 0.0043

= 4.3 ×
`10^(-3)` kg

Total mass of drug = 0.00019 + 0.0043

= 0.00449

= 4.49 ×
`10^(-3)` kg

Total mass of mixture = 0.5 kg + 10 kg

= 10.5 kg

Percentage of the drug in the mixture =
`(4.49*10^(-3) )/(10.5)` × 100

= 0.04276%

The percentage of the drug in the mixture is 0.043%.