Which are valid ways to make an ammonia/ammonium buffer for use in the laboratory?

See the explanation below, please.

Explanation:

A buffer solution (also called buffer / regulatory solution) corresponds to a mixture of high concentrations of an acid with its conjugate base, which allows maintenance of the pH when amounts of strong acids or strong bases are added. A buffer solution can be NH3 / ClNH4 (ammonia which is the base, and ammonium chloride, the acid).

  For example, to prepare said buffer, X volume of deionized water is placed, the ammonium chloride to be used is measured on an analytical scale, then dissolved in water, using a stirrer. On the other hand, ammonium hydroxide is added in volume X of deionized water. Both solutions are combined, increasing the flask. The pH is measured using a pH meter.

when the volume of gas is   changed from   717.73 ml   to 852 ml   the temperature will   change   from 315   c to 452   c

    calculation

this is calculated using the charles law formula

that is,   v1/t1 = v2/t2

          v1=?

        t1 = 315 c   into   kelvin = 315 +273 = 588 k

        v2 = 852   ml

        t2 = 425c + 273 =698 k

make v1   the subject of the formula ( by   multiplying both side by t1)

  v1=( v2 xt1) / t2

v1= (852 ml   x 588 k)/ 698 k= 717.73 ml