Question

Question #ab103

Answer 1

`"70 g"`

Explanation:

The idea here is that the density of the object tells you the mass of `"1 cm"^3` of this object.

In this case, you know that the density is equal to `"7.2 g cm"^(-3)`, which means that `"1 cm"^3` of this object has a mass of `"7.2 g"`.

This implies that your sample will have a mass of

`10 color(red)(cancel(color(black)("cm"^3))) * "7.2 g"/(1color(red)(cancel(color(black)("cm"^3)))) = "72 g"`

Now, notice that you have one significant figure for the volume of the object. This implies that the answer must be rounded to one significant figure.

`"mass" = color(darkgreen)(ul(color(black)("70 g")))`