What is the mass of a magnesium block that measures 2.5cm x 3.5cm x 1.5cm?

22.8 g

Explanation:

1) density = mass / volume ⇒ mass = density × volume

2) density of magnesium = 1.74 g/cm³ (from internet)

3) volume of a block = length × width × depth

  volume of the magnesium block = 2.5cm × 3.5 cm × 1.5 cm = 13.125 cm³

4) mass of the magnesium block = 1.74 g/cm³ × 13.125 cm³ = 22.8375 g.

Rounding to 3 significant figures, mass = 22.8 g ← answer

The mass of the magnesium block is found to be 22.8 g.

Density of a substance is defined as mass per unit volume.

Calculate the volume V of the magnesium block using the dimensions given in the problem.

Magnesium has a density ρ of 1.74g/cm³. This can be taken from the standard tables.

Since density is mass per unit volume,

The mass of the block is therefore given by,

Substitute  1.74g/cm³for  ρ and 13.125 cm³for V.

The mass of the magnesium block is found to be 22.8 g.

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.