Explain why the urine of a diabetic patient gives an intense brick red precipitation with Benedict's reagent whiles the urine of a normal person hardly from a precipitate

This is because of the presence of a lot of sugar in the diabetic patient's blood stream.

Explanation:

As a test for the presence of simple sugars, Benedict's solution is usually added to the test sample and then heated.

A diabetic patient's body system has a lot of sugar flowing around in the blood stream. His body is unable to get this sugar into the cells for use, because the insulin produced by his pancreas is not enough. As a result his body system has a lot of sugar.

Consequently, whenever the patient urinates, the urine has a high sugar content as opposed to a normal person, whose urine has a low sugar content because of a normal functioning body system.

The high sugar content of the diabetic patient's urine is what gives an intense brick red precipitation with Benedict's reagent.