Questions

The compound MgCl2 is named as Magnesium Chloride.

An Element is a pure substance of one type of atom. In chemistry, any material such as carbon, hydrogen, iron, or oxygen that cannot be broken down into more fundamental substances is nothing but an element.

As against malloc(), calloc() needs two arguments, the number of elements  to be allocated and the size of each element. For example,

 p = (int *) calloc (10, sizeof (int));

would allocate space for a 10- integer array. Additionally, calloc() would also set each of this element with a value 0.

Thus the above call to calloc() is equivalent to:

p = (int *) malloc (10 * sizeof (int));

memset (p, 0, 10 * sizeof( int ));