A 50.0 mL graduated cylinder has a mass of 53.6 g.

Question

A 50.0 mL graduated cylinder has a mass of 53.6 g. When it is filled with an unknown liquid to the 36.3 mL mark, the cylinder and liquid combined have a mass of 108.2 g. Calculate the density of the liquid in g/cm³. (1 mL = 1 cm³.)

Answer 1

I can help you out with this problem!

Before I begin, remember that density is equal to mass/volume.

So what you want to do first is to subtract the total weight by the weight of the beaker in order to get you the weight of just the liquid only. Therefore, 108.2 g - 53.6 g = 54.6 grams, which is the weight of the liquid in the beaker.

We have the mass part, now we need the volume.

Since the liquid goes up to the 36.3 ml mark, the volume is 36.3 ml. However, we need to convert it to cm^3.

Fortunately, 1 ml is equal to 1 cm^3. In fact, if you have seen medical dramas such as Grey's Anatomy, if you pay attention carefully, you will notice that they say "Give me 20ccs of so-and-so drug", they say this because 1 cc is short for cm^3, which is also 1ml. Just a fun fact right there to make learning easier!

So now, we will divide the mass of the liquid by the volume of the liquid, which is 54.6g/36.3cm^3 to get a final density of 1.50 g/cm^3.