What is the concentration of a solution in mg/mL if you dissolve 300 mg of a substance in 150 mL of water?

To determine the concentration of a solution in mg/mL, you divide the amount of the substance in milligrams by the volume of the solution in milliliters.

In this case, you start with 300 mg of the substance and dissolve it in 150 mL of water. The calculation for concentration can be expressed as follows:

Concentration (mg/mL) = Amount of substance (mg) / Volume of solution (mL)

When you perform the division:

Concentration = 300 mg / 150 mL

Concentration = 2 mg/mL

This reveals that the solution has a concentration of 2 mg/mL, which corresponds to the answer.

It's important to understand that concentration is a way of expressing how much of a solute is present in a given volume of solvent. In this calculation, we see that for every 1 mL of solution, there are 2 mg of the dissolved substance. Thus, the correct answer accurately reflects this ratio.