State Hess’ Law in words.
Write the balanced equation for this reaction.
Calculate the amount of heat given out in experiment 1, and include your units. Use the relevant Data Booklet data and assume that every solution has the same specific heat capacity as water.
Use your answer to (ii) to find the enthalpy change per mole of K$_2$CO$_3$. Give your answer in kJ mol$^{-1}$ and include a sign in your response.
Explain why the hydrochloric acid has to be in excess.
Write the balanced equation for this reaction.
Calculate the amount of heat taken in during experiment 2.
Use your answer to (ii) to find the enthalpy change per mole of KHCO$_3$. Give your answer in kJ mol$^{-1}$ and include a sign in your response.
On heating, KHCO$_3$ decomposes to give K$_2$CO$_3$, CO$_2$ and H$_2$O. $2\text{KHCO}_3 \rightarrow \text{K}_2\text{CO}_3 + \text{CO}_2 + \text{H}_2\text{O}$. Apply Hess’ Law together with your answers to (b)(iii) and (c)(iii) to determine the enthalpy change for this reaction. Give your answer in kJ mol$^{-1}$ and include a sign in your response.