More modern fireworks replace potassium nitrate with potassium chlorate. The thermochemical equation for the decomposition of potassium chlorate is shown in Equation 1. Often a catalyst is added to speed up this reaction.

Equation 1: 2KClO3(s) = 2KCl(s) + 3O2(g) ?H = -89.4 kJ mol-1

For reaction 1 draw a fully labelled diagram to show the internal energy changes during this process. On the same diagram show the effect the presence of a catalyst would have on the reaction.

(b) Pollution from fireworks occurs in a number of ways, one of which is the release of gases such as carbon dioxide and sulfur dioxide into the environment.

These gases react further in the atmosphere to produce carbonic acid (H2CO3), a weak acid and sulfuric acid (H2SO4) a strong acid. If the same number of moles of each of these acids were dissolved in equal volumes of water state, explain which of the resulting solutions would have the higher pH. Your answer should include an explanation of the pH scale and the changes that take place when each compound is dissolved in water.