Describe and explain the pattern in reactivity of magnesium, calcium and barium with cold water.
Give the equation for magnesium reacting with cold water.
Suggest why the water becomes cloudy eventually during the reaction of magnesium with cold water.
Suggest the equation for hot magnesium reacting with steam.
Give the equation for the reaction of magnesium oxide with nitric acid.
State the trend in thermal stability of the nitrates of Group II.
Give the equation for the thermal decomposition of magnesium nitrate.
By identifying any changes in oxidation number, explain which element is reduced and which is oxidised in the thermal decomposition of potassium nitrate, given by $2\text{KNO}_3 \rightarrow 2\text{KNO}_2 + \text{O}_2$.
Explain why magnesium oxide has such a high melting point.
Write equations to show how calcium carbonate can be changed into calcium hydroxide by a two-step process.
Write an ionic equation for the neutralisation reaction between hydrogen ions, $\text{H}^+$, and carbonate ions, $\text{CO}_3^{2-}$.
Use your equation to calculate the mass of powdered calcium carbonate that must be added to the pond to neutralise the acidity. The pond has a total volume of $8000\ \text{dm}^3$ and a pH of $4$, so the concentration of hydrogen ions is $1 \times 10^{-4}\ \text{mol dm}^{-3}$.