(a)[1]
Explain why effervescence is observed in the reaction.
(b(i))[1]
What colour would the methyl orange indicator show in the hydrochloric acid?
(b(ii))[1]
Calculate the amount of hydrochloric acid, in moles, that was used.
(b(iii))[1]
Use your answer to (b)(ii) and the equation for the reaction to work out the number of moles of sodium carbonate that reacted.
(b(iv))[2]
Use your answer to (b)(iii) to find the concentration of the sodium carbonate solution in mol/dm$^3$.
(c)[3]
Calculate the greatest volume (at r.t.p.) of carbon dioxide gas that could be produced in this reaction.