Answer: 0.5 g/ml
Step-by-step explanation:
The density of a substance is obtained by dividing its mass by the volume of water when it is placed in a vessel. Hence, its unit is gram per millilitre (g/ml)
Recall that volume of water in the graduated cylinder = 100 milliliters
Mass of rock = 50 grams
Density = Mass of rock ➗ volume of water
= 50 grams ➗ 100 milliliters
= 0.5 grams per millilitre
Thus, the density of the 50 grams rock in 100 milliliters of water is 0.5 g/ml