s-Block Elements Practice

Take timed practice tests on s-Block Elements for JEE Main and JEE Advanced with session-wise drills, score review, and explanation-led revision.

Timer-based practiceDetailed answer reviewMobile-friendly flow

Chemistry/s-Block Elements/ Practice

s-Block Elements Practice Tests

Six 20-question timed sessions plus a 60-question chapter module. Each item is original and reframed for copyright safety.

Ready

JEE Main Session 1

2Questions

60s/QTimer

+4 / -1Scoring

Preview all 8 questions in JEE Main Session 1 (no login required)

Alkali metals
1. Which of the following is NOT a property of alkali metals (Group 1)?
- A. They have high ionisation energy (Correct)
- B. They are soft metals
- C. They react with water
- D. They form +1 ions
Explanation: Alkali metals have the LOWEST ionisation energies in their periods (they readily lose one electron to form M⁺). They are soft, have low melting points, and react vigorously with water: 2M + 2H₂O → 2MOH + H₂↑.
Lithium anomaly
2. Lithium resembles magnesium (diagonal relationship) because both:
- A. Have similar charge-to-size ratio (charge density) (Correct)
- B. Have same electronic configuration
- C. Are in the same group
- D. Form the same hydrides
Explanation: Li⁺ and Mg²⁺ have similar ionic radii and charge densities → similar polarising power → form similar types of compounds. Both form covalent-character organometallic compounds, both carbonates decompose on heating, etc.
Alkaline earth metals
3. Beryllium (Be) is anomalous in Group 2 because:
- A. It forms covalent compounds (high charge density, small size, no d-orbitals) (Correct)
- B. It is radioactive
- C. It has +1 oxidation state
- D. It reacts explosively with water
Explanation: Be²⁺ has very high charge density (small size + 2+ charge). It polarises anions strongly → forms covalent compounds (BeCl₂ is covalent, unlike MgCl₂ which is ionic). Be also shows amphoteric behaviour unlike other Group 2 metals.
Flame test
4. The flame test colours for Na and K are:
- A. Na: golden yellow; K: lilac/violet (Correct)
- B. Na: red; K: yellow
- C. Na: blue; K: green
- D. Na: white; K: orange
Explanation: Flame test colours: Li (crimson red), Na (golden yellow), K (lilac/violet), Rb (red-violet), Cs (blue). Na contaminates K tests — use cobalt blue glass to filter yellow and see lilac of K.
Compounds
5. Washing soda (Na₂CO₃·10H₂O) loses water on exposure to air. This process is called:
- A. Efflorescence (Correct)
- B. Deliquescence
- C. Hygroscopy
- D. Sublimation
Explanation: Efflorescence: loss of water of crystallisation on exposure to air. Na₂CO₃·10H₂O (washing soda) → Na₂CO₃·H₂O (white powder). Deliquescence: absorption of moisture from air to form solution (NaOH, CaCl₂).
JEE Main
6. Quick lime (CaO) reacts with water to give:
- A. Ca(OH)₂ (slaked lime) with evolution of heat (Correct)
- B. CaCO₃
- C. Ca + H₂
- D. CaO + H₂O (no reaction)
Explanation: CaO + H₂O → Ca(OH)₂ + heat (exothermic). This is slaking of lime. Ca(OH)₂ is slaked lime (or milk of lime when suspended in water). Used in plastering, water treatment, and making bleaching powder.
Mixed
7. The correct order of solubility of alkaline earth metal sulphates in water is:
- A. BeSO₄ > MgSO₄ > CaSO₄ > SrSO₄ > BaSO₄ (Correct)
- B. BaSO₄ > SrSO₄ > CaSO₄ > MgSO₄ > BeSO₄
- C. All equally soluble
- D. Depends only on temperature
Explanation: Sulphate solubility decreases down Group 2: BeSO₄ (soluble) → MgSO₄ (soluble) → CaSO₄ (sparingly soluble) → SrSO₄ (insoluble) → BaSO₄ (insoluble, used in X-ray barium meal). Lattice energy decreases faster than hydration energy down the group.
Mixed
8. Bleaching powder (CaOCl₂ or Ca(OCl)Cl) on treatment with CO₂ releases:
- A. Cl₂ gas (which does the bleaching) (Correct)
- B. CO₂ remains unchanged
- C. CaCO₃ + HCl
- D. Ca(OH)₂ + Cl₂
Explanation: Bleaching powder + dilute acid/CO₂: Ca(OCl)Cl + CO₂ + H₂O → CaCO₃ + Cl₂ + H₂O (or with HCl → CaCl₂ + H₂O + Cl₂). The liberated Cl₂ oxidises coloured matter → bleaching. The reaction with CO₂ in air explains why bleaching powder loses potency on storage.

Loading practice engine...

JEE Main Session 1

2Questions

60s/QTimer

+4 / -1Scoring

Preview all 8 questions in JEE Main Session 1 (no login required)

Alkali metals
1. Which of the following is NOT a property of alkali metals (Group 1)?
- A. They have high ionisation energy (Correct)
- B. They are soft metals
- C. They react with water
- D. They form +1 ions
Explanation: Alkali metals have the LOWEST ionisation energies in their periods (they readily lose one electron to form M⁺). They are soft, have low melting points, and react vigorously with water: 2M + 2H₂O → 2MOH + H₂↑.
Lithium anomaly
2. Lithium resembles magnesium (diagonal relationship) because both:
- A. Have similar charge-to-size ratio (charge density) (Correct)
- B. Have same electronic configuration
- C. Are in the same group
- D. Form the same hydrides
Explanation: Li⁺ and Mg²⁺ have similar ionic radii and charge densities → similar polarising power → form similar types of compounds. Both form covalent-character organometallic compounds, both carbonates decompose on heating, etc.
Alkaline earth metals
3. Beryllium (Be) is anomalous in Group 2 because:
- A. It forms covalent compounds (high charge density, small size, no d-orbitals) (Correct)
- B. It is radioactive
- C. It has +1 oxidation state
- D. It reacts explosively with water
Explanation: Be²⁺ has very high charge density (small size + 2+ charge). It polarises anions strongly → forms covalent compounds (BeCl₂ is covalent, unlike MgCl₂ which is ionic). Be also shows amphoteric behaviour unlike other Group 2 metals.
Flame test
4. The flame test colours for Na and K are:
- A. Na: golden yellow; K: lilac/violet (Correct)
- B. Na: red; K: yellow
- C. Na: blue; K: green
- D. Na: white; K: orange
Explanation: Flame test colours: Li (crimson red), Na (golden yellow), K (lilac/violet), Rb (red-violet), Cs (blue). Na contaminates K tests — use cobalt blue glass to filter yellow and see lilac of K.
Compounds
5. Washing soda (Na₂CO₃·10H₂O) loses water on exposure to air. This process is called:
- A. Efflorescence (Correct)
- B. Deliquescence
- C. Hygroscopy
- D. Sublimation
Explanation: Efflorescence: loss of water of crystallisation on exposure to air. Na₂CO₃·10H₂O (washing soda) → Na₂CO₃·H₂O (white powder). Deliquescence: absorption of moisture from air to form solution (NaOH, CaCl₂).
JEE Main
6. Quick lime (CaO) reacts with water to give:
- A. Ca(OH)₂ (slaked lime) with evolution of heat (Correct)
- B. CaCO₃
- C. Ca + H₂
- D. CaO + H₂O (no reaction)
Explanation: CaO + H₂O → Ca(OH)₂ + heat (exothermic). This is slaking of lime. Ca(OH)₂ is slaked lime (or milk of lime when suspended in water). Used in plastering, water treatment, and making bleaching powder.
Mixed
7. The correct order of solubility of alkaline earth metal sulphates in water is:
- A. BeSO₄ > MgSO₄ > CaSO₄ > SrSO₄ > BaSO₄ (Correct)
- B. BaSO₄ > SrSO₄ > CaSO₄ > MgSO₄ > BeSO₄
- C. All equally soluble
- D. Depends only on temperature
Explanation: Sulphate solubility decreases down Group 2: BeSO₄ (soluble) → MgSO₄ (soluble) → CaSO₄ (sparingly soluble) → SrSO₄ (insoluble) → BaSO₄ (insoluble, used in X-ray barium meal). Lattice energy decreases faster than hydration energy down the group.
Mixed
8. Bleaching powder (CaOCl₂ or Ca(OCl)Cl) on treatment with CO₂ releases:
- A. Cl₂ gas (which does the bleaching) (Correct)
- B. CO₂ remains unchanged
- C. CaCO₃ + HCl
- D. Ca(OH)₂ + Cl₂
Explanation: Bleaching powder + dilute acid/CO₂: Ca(OCl)Cl + CO₂ + H₂O → CaCO₃ + Cl₂ + H₂O (or with HCl → CaCl₂ + H₂O + Cl₂). The liberated Cl₂ oxidises coloured matter → bleaching. The reaction with CO₂ in air explains why bleaching powder loses potency on storage.