Acid and Bases MCQs

21. Which gas is released when acid reacts with metal?
A) Oxygen
B) Hydrogen
C) Nitrogen
D) Carbon dioxide
Answer: B

22. Which compound is amphoteric?
A) NaCl
B) Al(OH)₃
C) HCl
D) NaOH
Answer: B

23. Which acid is strongest?
A) HCl
B) CH₃COOH
C) H₂CO₃
D) HF
Answer: A

24. Which base turns red litmus blue?
A) Acid
B) Base
C) Salt
D) Neutral
Answer: B

25. What is the chemical formula of nitric acid?
A) H₂SO₄
B) HCl
C) HNO₃
D) CH₃COOH
Answer: C

26. What is the chemical formula of sulfuric acid?
A) HCl
B) H₂SO₄
C) HNO₃
D) H₂CO₃
Answer: B

27. Which acid is present in ant stings?
A) Acetic acid
B) Formic acid
C) Citric acid
D) Lactic acid
Answer: B

28. Which base is used in whitewashing?
A) NaOH
B) KOH
C) Ca(OH)₂
D) NH₄OH
Answer: C

29. What is the pH of pure water?
A) 5
B) 6
C) 7
D) 8
Answer: C

30. Which salt is formed from HCl and NaOH?
A) Na₂SO₄
B) NaCl
C) KCl
D) NH₄Cl
Answer: B