Question

Complete this sentence. If mass remains the same while the volume of a substance ________, the density of the substance will_______________.

decreases, increase
increases, increase
increases, stay the same
decreases, stay the same

Answer 1

density = mass/volume

mass is constant as stated by the problem. if volume changes, the density should change somehow, eliminating choices 3 and 4.

finally let's try deciding between choice 1 vs 2.

1. the volume decreases. if the volume decreases, the denominator in the density equation decreases. therefore, the overall value of the fraction increases. so the density increases. this is the only viable answer choice.