An object with a mass of 12.59 grams was immersed in water in a graduated cylinder. The volume of the water before was 56.7 mL. After the object was placed in the water, the volume read 63.0 mL. If density = mass/volume, calculate the density of the object to the correct sig figs.

Explanation:

The density is the mass per unit volume. It is calculated using the following formula.

The mass of the object is 12.59 grams.

The volume was found using water displacement. A known quantity of water was placed in a graduated cylinder (56.7 mL), then the object was added and the water level was recorded again (63.0 mL)The volume of the object is the difference between the initial water volume and the final water volume.

Now we know the mass and volume of the object and we can substitute the values into the formula.

Divide.

The original measurements have 4 and 3 significant figures. We always round our answer to the least number of sig figs, which is 3. For the number we found, that is the hundredth place. The 8 in the thousandth place tells us to round the 9 up to a 0 (hundredth place), then the 9 up to a 0 (tenth place), and the 1 up to a 2 (ones place).

The density of the object is approximately 2.00 grams per milliliter.