(a(i))[1]
State which negative ion has the greatest mass in $1000\,\text{cm}^3$ of fruit juice.
(a(ii))[1]
Give the formulae for the ions present in sodium nitrate.
(a(iii))[1]
Calculate the mass of ammonium ions in $250\,\text{cm}^3$ of fruit juice.
(b)[2]
Describe a test for chloride ions.
(c(i))[2]
State the names of two other elements found in most fertilisers.
(c(ii))[1]
Explain why farmers apply fertilisers to fields before crops are grown.
(d(i))[2]
Complete the equation for this reaction.\n\n$(\text{NH}_4)_2\text{SO}_4 + \ldots\text{NaOH} \rightarrow \ldots\text{NH}_3 + \text{Na}_2\text{SO}_4 + 2\text{H}_2\text{O}$
(d(ii))[3]
Initially, the red litmus paper remains red. After a little while, the litmus paper turns blue. Explain these observations using the kinetic particle model.