If 5mL of ethenal has mass of 3.9g and 5.0 mL of benzine has mass 44g. Which is denser?

To determine which substance is denser, we can calculate the density of each. The density of ethenal is 3.9 g / 5 mL = 0.78 g/mL, while the density of benzine is 44 g / 5 mL = 8.8 g/mL. Since 8.8 g/mL (benzine) is greater than 0.78 g/mL (ethenal), benzine is denser than ethenal.