What is the weight of 7.9 ml of a solution that has a density of 1.1 g/mL?

8.69 g

Explanation:

density = 1.1 g/mL

it means,

1 ml of the solution has a mass of 1.1 g

∴7.9 ml of the solution has a mass of = (1.1 x7.9) g

=8.69 g

Since the equation for density is d=m/v, you can multiply both sides by m in order to get m by itself {d (v) = m}. Plug the volume and density in (1.1x7.9) and you will get 8.69. If you are using proper sig figs, then it will be 8.7g.