(a)[3]
Calculate the volume of nitrogen produced when a $25.0\,\text{cm}^3$ portion of $0.133\,\text{mol dm}^{-3}$ $\text{NH}_4\text{NO}_2$ fully decomposes. Measure the volume at room temperature and pressure. Give your answer to two significant figures.
(b)[2]
Describe and explain how increasing the temperature affects the rate of this reaction.
(c)[2]
Describe and explain the effect of lowering the concentration of ammonium nitrite on the rate of this reaction.
(d)[2]
Besides using a pH meter, describe one more method for measuring the pH of aqueous ammonium nitrite.