Question

Select the valid ways to make an ammonia/ammonium buffer for use in the laboratory. Mix equal volumes of 1 M NH3 and 0.01 M NH 4. Mix some volume of 1 M NH3 with half as much 1 M HCl. Mix equal volumes of 1 M NH3 and 1 M NH 4. Mix equal volumes of 1 M NH3 and 1 M HCl.

Answer 1

Answer:

The answer is "Option b and Option c".

Explanation:

This buffer is a buffer of ammonia and ammonium ion. Thus it requires the solution $NH_3 \ \ and \ \ NH_4^{+}$.

In point 1:

The solution containing $NH_3 \ \ and \ \ NH_4^{+}$ at 1M concentration would be given by mixing the two solutions. Thus, this buffer is a legitimate route.

In point 2:

It gives the ions you want but they are not the same.

In point 3:

$1 M$ $NH_3$ and $1 M$$HCl$ volume would not produce the same $NH_3 \ \ and \ \ NH_4^{+}$ concentrations. Therefore, this buffer isn't a valid route.

In point 4:

Some $1 M$ $NH_3$ volume and half $HCl$ . This offers the same rate as half.