(a(i))[1]
Calculate the mass of magnesium ions in the 1000 cm^{3} sample of mineral water.
(a(ii))[1]
Which negative ion has the greatest concentration?
(a(iii))[1]
State the name given to the ion $\text{NO}_3^-$.
(a(iv))[1]
Calculate the mass of hydrogencarbonate ions in 250 cm^{3} of this sample.
(b)[2]
Describe a test for ammonia gas. Include both the test and the result.
(c)[1]
Deduce the formula for calcium bromide.
(d(i))[2]
Predict the products formed at the negative electrode (cathode) and the positive electrode (anode) in this electrolysis.
(d(ii))[1]
Give the name of one other substance that can be used to make an inert electrode.