Chemistry • Year 11 • Module 3 • Lesson 5
Acid-Base & Acid-Carbonate Reactions
Lock in the core vocabulary, reaction-type recognition, salt identification rules, and the SWC mnemonic before tackling exam questions.
1. Term–definition match
Write the matching term from this list into the right-hand column. Terms: acid, base, alkali, neutralisation, salt, net ionic equation, carbonate, acid-carbonate reaction, SWC products, Arrhenius definition. 10 marks (1 each)
| # | Definition | Matching term |
|---|---|---|
| 1.1 | A substance that produces H+ ions in water (Arrhenius) or donates a proton (Brønsted-Lowry). | |
| 1.2 | A substance that produces OH− ions in water (Arrhenius) or accepts a proton (Brønsted-Lowry). | |
| 1.3 | A soluble base that forms OH− ions in water; e.g. NaOH, Ca(OH)2. | |
| 1.4 | The reaction between an acid and a base: acid + base → salt + water. | |
| 1.5 | An ionic compound formed from the cation of a base and the anion of an acid. | |
| 1.6 | Shows only the ions that actually change during a reaction; spectator ions are removed. | |
| 1.7 | An ion with the formula CO32−; its presence leads to the formation of CO2 gas when treated with acid. | |
| 1.8 | Acid + carbonate → salt + water + CO2(g); three products always formed. | |
| 1.9 | The memory aid that lists the three fixed products of every acid-carbonate reaction: Salt, Water, Carbon dioxide. | |
| 1.10 | The model proposed in 1884 stating that acids produce H+ and bases produce OH− in water. |
2. True or false, with correction
Circle T or F. If false, write the corrected statement on the line. 10 marks (1 T/F + 1 correction)
2.1 The net ionic equation for any strong acid reacting with any strong base is H+(aq) + OH−(aq) → H2O(l). T / F
2.2 When an acid reacts with a carbonate, CO(g) is produced as the gaseous carbon product. T / F
2.3 The salt formed when HCl reacts with NaOH is NaCl (sodium chloride). T / F
2.4 Mylanta (active ingredient: Mg(OH)2) produces CO2 gas when it neutralises stomach acid. T / F
2.5 The anion of the salt in any neutralisation reaction always comes from the base. T / F
3. Identify the salt and reaction type
For each acid-base pair, state (a) the reaction type, (b) the name and formula of the salt formed, and (c) one other product. Do not write the balanced equation yet, just identify. 12 marks (2 each)
3.1 HNO3(aq) + KOH(aq) →
(a) Reaction type:
(b) Salt name and formula:
(c) Other product(s):
3.2 H2SO4(aq) + Ca(OH)2(aq) →
(a) Reaction type:
(b) Salt name and formula:
(c) Other product(s):
3.3 HCl(aq) + CaCO3(s) →
(a) Reaction type:
(b) Salt name and formula:
(c) Other product(s):
3.4 HNO3(aq) + Na2CO3(aq) →
(a) Reaction type:
(b) Salt name and formula:
(c) Other product(s):
3.5 HCl(aq) + NaHCO3(aq) →
(a) Reaction type:
(b) Salt name and formula:
(c) Other product(s):
3.6 H2SO4(aq) + 2NaOH(aq) →
(a) Reaction type:
(b) Salt name and formula:
(c) Other product(s):
4. Cloze, fill the blank
Complete the paragraph using the word bank. Each term is used once only. 8 marks (1 per blank)
Word bank: neutralisation • salt • water • CO2 • spectator • SWC • H+ • OH−
When an acid reacts with a base, the process is called _______________ (1). The H+ ion from the acid combines with the _______________ (2) ion from the base to form _______________ (3). The remaining ions form a _______________ (4). Because the Na+ and Cl− ions in, say, HCl + NaOH do not change during the reaction, they are called _______________ (5) ions and are removed from the net ionic equation. The universal net ionic form is therefore _______________ (6) + OH− → H2O.
When acid meets a carbonate, the mnemonic _______________ (7) lists the three products: salt, water, and _______________ (8) gas.
5. Build a concept map
Draw labelled arrows between the five terms below to show how they connect. Each arrow must carry a linking phrase (e.g. "produces", "is a type of", "reacts with"). Aim for at least 5 labelled arrows. 5 marks
Supplied terms: acid • base • salt • carbonate • CO2.
Q1, Term-definition matches
1.1 acid • 1.2 base • 1.3 alkali • 1.4 neutralisation • 1.5 salt • 1.6 net ionic equation • 1.7 carbonate • 1.8 acid-carbonate reaction • 1.9 SWC products • 1.10 Arrhenius definition.
Q2, True / false with correction
2.1 True. H+(aq) + OH−(aq) → H2O(l) is universal for all strong acid-strong base reactions.
2.2 False. Correction: The gas produced is CO2 (carbon dioxide), not CO. The carbon in CO32− is already at oxidation state +4, so only CO2 is possible.
2.3 True. Na+ (from base) + Cl− (from acid) = NaCl.
2.4 False. Correction: Mg(OH)2 is a hydroxide base, not a carbonate. It undergoes neutralisation (acid + base → salt + water) and produces NO CO2.
2.5 False. Correction: The anion of the salt comes from the acid, not the base. The cation comes from the base.
Q3, Salt identification
3.1 (a) Neutralisation. (b) Potassium nitrate, KNO3. (c) Water, H2O(l).
3.2 (a) Neutralisation. (b) Calcium sulfate, CaSO4. (c) Water, H2O(l).
3.3 (a) Acid-carbonate reaction. (b) Calcium chloride, CaCl2. (c) Water, H2O(l) and carbon dioxide, CO2(g).
3.4 (a) Acid-carbonate reaction. (b) Sodium nitrate, NaNO3. (c) Water, H2O(l) and carbon dioxide, CO2(g).
3.5 (a) Acid-hydrogen carbonate reaction. (b) Sodium chloride, NaCl. (c) Water, H2O(l) and carbon dioxide, CO2(g).
3.6 (a) Neutralisation. (b) Sodium sulfate, Na2SO4. (c) Water, H2O(l).
Q4, Cloze answers
(1) neutralisation • (2) OH− • (3) water • (4) salt • (5) spectator • (6) H+ • (7) SWC • (8) CO2.
Q5, Sample concept map
Acceptable labelled arrows include:
- acidreacts with → baseto produce → salt
- acidreacts with → carbonateto produce → salt
- carbonatewhen reacting with acid releases → CO2
- carbonateis a type of → base
- basedoes not produce → CO2 (distinguishing arrow)
Award 1 mark per correctly labelled arrow that respects causal direction. Five arrows required for full marks.