Describe how the triple covalent bond is formed in a N$_2$(g) molecule. Refer to orbital overlap and hybridisation in your answer.
Nitrogen oxides, NO$_2$ and NO, are formed in internal combustion engines. Releasing these gases into the atmosphere causes photochemical smog to form. Outline how nitrogen oxides are involved in the formation of photochemical smog.
Construct an equation to show how a catalytic converter lowers the amount of nitrogen oxide gases released into the atmosphere.
N$_2$(g) is very unreactive. It is difficult to produce ammonia, NH$_3$(g), directly from its elements but it can be made from NH$_4$Cl(s). Identify a reagent and the conditions needed to make NH$_3$(g) from NH$_4$Cl(s).
25 cm$^3$ of $0.10\,\text{mol dm}^{-3}$ HCl(aq) is placed in a beaker and its pH is noted. 50 cm$^3$ of $0.10\,\text{mol dm}^{-3}$ NH$_3$(aq) is added to the HCl(aq) in $5\,\text{cm}^3$ portions. The pH of the mixture is watched until all the NH$_3$(aq) has been added. HCl is a strong Brønsted-Lowry acid. Describe what is meant by a strong Brønsted-Lowry acid.
NH$_3$ is a weak base. Construct an equation showing the behaviour of NH$_3$ as a weak Brønsted-Lowry base when it is dissolved in water.
On Fig. 2.1 sketch a graph to show the pH change that occurs when HCl(aq) is titrated with NH$_3$(aq) as described in (d).