The relative density of a solid is 6.5. Find (1)the mass of a solid substance cube of side 20cm. (2) the volume of the substance if the mass is 1.3kg

20^3 = 2^3 * 10^3 = 8,000

6.5 g/cm^3 * 8,000 cm^3 = 52,000grams = 52 Kg

1300g * (1 cm^3/6.5g) = 200 cm^3

To find the mass of the solid substance cube, we can use the formula:

Mass = Relative density x Volume

Given that the relative density of the solid is 6.5 and the side length of the cube is 20 cm, we can calculate the volume of the cube.

Volume = (side length)^3

Calculating the volume:

Volume = (20 cm)^3
= 20 cm x 20 cm x 20 cm
= 8000 cubic cm

Now, we can find the mass:

Mass = Relative density x Volume
= 6.5 x 8000 cubic cm
= 52,000 grams (since 1 cubic cm = 1 gram)

Therefore, the mass of the solid substance cube is 52,000 grams.

To find the volume of the substance if the mass is 1.3 kg, we can rearrange the formula:

Volume = Mass / Relative density

Given that the mass is 1.3 kg and the relative density is 6.5, we can calculate the volume:

Volume = 1.3 kg / 6.5
= 0.2 liters (since 1 kg = 1 liter)

Therefore, the volume of the substance is 0.2 liters.