Question

What is the percent concentration of a drug if 255 mg of the drug is found in 650 mL? Round your final answer to 3 decimal places if necessary.

Answer 1

1) List the known values.

Solute: 255 mg

Solution: 650 mL

Unknown

Percent concentration:

2) Set the equation

$\frac{mass}{volume}\%=\frac{grams\text{ }of\text{ }solute}{milliliters\text{ }of\text{ }solution}*100$

Convert milligrams to grams

1 g = 1000 mg

$g=255mg*\frac{1g}{1000mg}=0.255g$

3) Plug in known values.

$\frac{mass}{volume}\%=\frac{0.255g\text{ }of\text{ }solute}{650\text{ }mL\text{ }of\text{ }solution}*100$$=0.039231\%$

The percent concentration of the drug is 0.039%(m/V)

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