Write the equation for calcium oxide reacting with water.
Identify the ion responsible for an aqueous solution being alkaline.
The table gives the melting points of some Group $2$ metal oxides. Explain the pattern in the melting points of the oxides down Group $2$.
Oxygen reacts readily with some metals, but each Group $2$ metal has to be heated strongly before it will react with oxygen. Suggest why strong heating is needed to start these reactions.
Beryllium oxide reacts with hydrochloric acid to produce molecules of $\text{BeCl}_2$. Deduce the bond angle in $\text{BeCl}_2$.
Unlike the other Group $2$ metal oxides, beryllium oxide is amphoteric. Give the meaning of amphoteric.
Beryllium oxide and aluminium oxide have similar chemical properties. The $\text{Be(OH)}_4^{2-}$ anion is formed when beryllium oxide reacts with excess concentrated $\text{OH}^-(aq)$. Write an equation for this reaction.
Magnesium oxide reacts reversibly with chlorine according to the equation $2\text{MgO}(s) + 2\text{Cl}_2(g) \rightleftharpoons 2\text{MgCl}_2(s) + \text{O}_2(g)$. Under certain conditions, a dynamic equilibrium is set up. State two features of a reaction that is in dynamic equilibrium.
The equilibrium constant, $K_p$, is defined by $K_p = \frac{p_{\text{O}_2}}{p_{\text{Cl}_2}^2}$. At $1.00 \times 10^5\ \text{Pa}$ and $500\ \text{K}$, $70\%$ of the starting amount of $\text{Cl}_2(g)$ has reacted. Calculate $K_p$ and give its units.
Magnesium peroxide, $\text{MgO}_2$, is produced in the reaction $\text{MgO}(s) + \text{H}_2\text{O}_2(l) \rightarrow \text{MgO}_2(s) + \text{H}_2\text{O}(l)$, $\Delta H = -96\ \text{kJ mol}^{-1}$. The peroxide ion is $\text{O}_2^{2-}$. Deduce the average oxidation number of oxygen in the peroxide ion.
Define the term enthalpy change of formation.
Use the data provided to calculate the enthalpy change of formation of $\text{MgO}_2(s)$.
Magnesium peroxide slowly breaks down to produce magnesium oxide and oxygen. $\text{MgO}_2(s) \rightarrow \text{MgO}(s) + \tfrac{1}{2}\text{O}_2(g)$ Use your answer to g(iii) and the data in the table to calculate the enthalpy change for this reaction. If you were unable to obtain an answer to g(iii), use the value $\Delta H_f = -550\,\text{kJ mol}^{-1}$. This is not the correct answer. enthalpy change of reaction $= \dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\,\text{kJ mol}^{-1}$