3. a soil sample has a volume of 75 cm3. after being saturated with water, it weighs 173.85 g. the sample is dried in an oven; the dry weight is 158.77 g. assume the density of water is 1.00 g/cm. find the porosity.

Porosity will be 20.107 %

Explanation:

Porosity is the portions of the rock or a sample which is not occupied by solid material. And this void space is generally filled up by liquids, such as ground water. Porosity of a sample is measured on the basis of volume of the pore space in the total volume of the sample.

We have given a soil has volume =

Its saturated weight is 173.85 gram

Oven dried weight is 158.77 gram

Therefore the weight of the water present in the pore space = 173.85 - 158.77 = 15.08 gram

Density of the water = 1

The volume of the water present in the pore space is = 15.08

Now, Porosity = , here  is volume of voids and is total volume

Porosity = = 20.107 %.