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chemistry igcse acapprinted 98 · PDF 98
145 pagesrevision 46934
printed 98 · PDF 98
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Practice Questions (Solved )
1. Explain the difference between an alkali and a base, and give examples of each.
Answer:
A base neutralizes acids and is insoluble , while an alkali is a base that dissolves in water to release
OH⁻ ions. For example, NaOH is an alkali, and CaCO₃ is a base.
2. Describe how you would carry out a titration to find the concentration of a sulfuric acid
solution using a standard solution of sodium hydroxide and an appropriate indicator.
Answer:
Measure NaOH with a pipette, add indicator, and titrate with H₂SO₄ from a burette until the
endpoint. Record the volume to calculate H₂SO₄ concentration.
3. Explain the amphoteric nature of aluminum oxide and describe its reactions with both acids and
bases.
Answer:
Al₂O₃ is amphoteric; it reacts with acids to form salts and with bases to form aluminate.
Practice Questions (Unsolved )
P2
1. Which of the following substances will turn red litmus paper blue?
A) Hydrochloric acid
B) Sodium hydroxide
C) Water
D) Ethanoic acid
2. Which of these reactions is a neutralization reaction?
A) HCl + NaOH → NaCl + H₂O
B) HCl + Mg → MgCl₂ + H₂
C) HCl + ZnCO₃ → ZnCl₂ + CO₂ + H₂O
D) H₂SO₄ + Cu → CuSO₄ + H₂
3. What type of oxide is formed when a non-metal reacts with oxygen?
A) Basic oxide
B) Acidic oxide