Which of the following is a fossil fuel? MCQ with Answer and Explanation

Which of the following is a fossil fuel?
A. Solar energy
B. Biogas
C. Hydrogen
D. Natural gas
Answer: Option D
Solution (By JKSSB Mock Tests)
Natural gas (mainly methane) is a fossil fuel formed from ancient organic matter. Biogas is a renewable fuel from recent organic waste. Hydrogen is an energy carrier, not a fossil fuel. Solar energy is renewable.

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More chemistry Questions

Question #1
Which of the following salts forms an acidic aqueous solution?
A. Sodium acetate
B. Ammonium chloride
C. Potassium nitrate
D. Sodium carbonate

Correct Answer: Option B


Explanation:
NH₄Cl is from strong acid (HCl) and weak base (NH₄OH). It hydrolyzes: NH₄⁺ + H₂O ⇌ NH₄OH + H⁺, making solution acidic (pH

This question belongs to: Science chemistry
Question #2
The pH of pure water at 25°C is 7. This is because:
A. It contains only OH⁻
B. It has no ions
C. It is a strong acid
D. It contains equal concentrations of H⁺ and OH⁻ ions

Correct Answer: Option D


Explanation:
Water self-ionizes: H₂O ⇌ H⁺ + OH⁻. At 25°C, [H⁺] = [OH⁻] = 10⁻⁷ mol/L, so Kw = 10⁻¹⁴ and pH = pOH = 7. A solution is neutral when [H⁺] = [OH⁻]. pH 7 is neutral only at 25°C; at higher temperatures, Kw increases, pH of neutrality drops but still [H⁺]=[OH⁻].

This question belongs to: Science chemistry
Question #3
Which of the following compounds contains a coordinate covalent bond?
A. Cl₂
B. NaCl
C. NH₄⁺
D. H₂O

Correct Answer: Option C


Explanation:
In the ammonium ion (NH₄⁺), the nitrogen atom in ammonia (NH₃) shares its lone pair of electrons with a hydrogen ion (H⁺) which has no electrons. This type of bond, where both shared electrons are donated by a single atom, is a coordinate covalent (dative) bond.

This question belongs to: Science chemistry