 Question Video: Calculating the Density of a Substance given Its Mass and Volume | Nagwa Question Video: Calculating the Density of a Substance given Its Mass and Volume | Nagwa

# Question Video: Calculating the Density of a Substance given Its Mass and Volume Science

A substance has a mass of 13.5 g and occupies a volume of 5 cm³. What is its density?

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### Video Transcript

A substance has a mass of 13.5 grams and occupies a volume of five centimeters cubed. What is its density?

Density is a value or number we give to a substance or object when we take its mass and divide this value by its volume. Mass is usually measured in grams, symbol lowercase g. And volume is usually measured in cubic centimeters, symbol cm to the power of three. Density has the unit grams per centimeter cubed, symbol g forward slash cm to the power of three.

We can define density as the amount of mass per unit volume in a substance. The density value of a substance tells us how compact the substance is. In other words, it tells us how closely the particles are packed. In a balloon, the air particles are not packed closely together. The particles are rather far apart. Air in balloons has a low density. The particles in a stone or an iron nail are closely packed. These objects have a high density.

The question asks us to determine the density of a substance. We are given its mass of 13.5 grams. And we are given its volume of five centimeters cubed. We can put these two values into the equation. We put 13.5 grams at the top for the mass and five centimeters cubed at the bottom for the volume. Then, we can divide the two numbers. This gives us an answer of 2.7.

Next, we can figure out what the units will be. We have grams at the top and centimeters cubed at the bottom. This gives us the unit grams per centimeter cubed in the answer. We have already seen that this is the unit for density. This unit is what we expected. So, the density of the substance is 2.7 grams per centimeter cubed.

Is this density value high or low? We cannot say by just looking at the answer. But we can compare it with the density of a substance we know. Water has an easy density value to remember. Water’s density is one gram per centimeter cubed. So the substance in the question has a density value bigger than the density of water. This means that if this substance was placed into water, and if it didn’t dissolve, it would sink.

Finally, what is the density of a substance with a mass of 13.5 grams and a volume of five centimeters cubed? The answer is 2.7 grams per centimeter cubed.