Question

The natural water content of a Boston Blue Clay soil sample was found to be 14.6% through oven drying. It has been calculated that the maximum density for the clay will be obtained when the water content of the soil reaches 21.2%. Compute how many grams of water must be added to each 500 grams of Boston Blue Clay (in its natural state) in order to increase the water content to 21.2%.

Answer 1

41.87 grams of water content must be added to each 500 grams of Boston Blue Clay (in its natural state) in order to increase the water content to 21.2%

Step-by-step explanation:

The natural water content in Boston Clay is 14.6%. Thus, in 500 grams of Boston clay, the amount of water, naturally present will be:

Natural Water Content = 14.6% of 500 grams

Natural Water Content = 0.146 x 500 grams

Natural Water Content = 73 grams

Thus, the amount of dry clay will be:

Dry Clay = 500 grams - 73 grams

Dry Clay = 427 grams

Now, the required water content is 21.2%, and thus, the remaining 78.8% will be the dry clay. The mass of dry clay is calculated to be 427 grams.

If, we let 'X' be the total mass of clay and water content after the water content is increased to 21.2%. Then;

427 grams = 78.8% of X

427 grams = (0.788)X

X = 427 grams/0.788

X = 541.87 grams

Now, the mass of water content added will be equal to the difference between the total mass of clay before addition of water content and total mass of clay after addition of water content.

Water content added = X - 500 grams

Water Content Added = 541.87 grams - 500 grams

Water Content Added = 41.87 grams