Question

Density is mass per unit of volume. Which pair of lab instruments would a student use to measure the density of seawater?

Answer 1

Answer:  C. a balance and a beaker

Explanation:

A balance would be used to measure the weight, which in turn effectively measures the mass (more or less). Imagine that we have a brick that we know is 1 pound. If we have an object that needs 5 bricks on one side to balance it out, then we know the object is 5 pounds.

The beaker is used to measure the volume. It's basically a measuring cup that you would find in the kitchen.

To get the density, you divide the mass over volume.

For example, if you have a material that has a mass of 100 grams and it's volume is 20 cm^3, then its density is 100/20 = 5 grams per cm^3.