The fuel with the highest calorific value per gram is:
A. Coal
B. Methane
C. Wood
D. Hydrogen
Answer: Option D
Solution (By JKExamLibrary)
Hydrogen has about 141.9 kJ/g, the highest of any fuel. Methane ~55.5 kJ/g, coal ~25-35 kJ/g, wood ~17 kJ/g. Hydrogen produces only water on combustion, making it a clean fuel.
Explanation:
Hard water contains dissolved Ca²⁺ and Mg²⁺ ions which react with soap to form insoluble scum, preventing lather. Soft water lathers readily. Distilled water is pure (soft). Rainwater is naturally soft but may dissolve CO₂ and become slightly acidic.
Explanation:
A galvanic (or voltaic) cell generates electrical energy from a spontaneous chemical reaction. The Daniel cell is a specific, classic type of galvanic cell using zinc and copper electrodes. An electrolytic cell does the reverse, using electrical energy to drive a non-spontaneous chemical reaction.
Explanation:
Ammonia (NH₃) is manufactured by the Haber process, which involves the direct combination of nitrogen and hydrogen gases at high pressure (200 atm) and moderate temperature (450°C) in the presence of an iron catalyst. The Contact process is for sulfuric acid, and Ostwald's is for nitric acid.
No comments yet. Be the first to start the discussion!