(a(i))[1]
Which negative ion has the greatest concentration?
(a(ii))[1]
Calculate the mass of potassium ions contained in 250 cm$^3$ of this solution.
(a(iii))[1]
Calculate the total mass of positive ions in 1000 cm$^3$ of this solution.
(a(iv))[1]
Give the name of the compound made from Na$^+$ and HCO$_3^-$ ions.
(b)[2]
Describe the observations in these two reactions. Excess aqueous sodium hydroxide is added to a solution containing Ca$^{2+}$ ions. Excess aqueous ammonia is added to a solution containing Ca$^{2+}$ ions.