Which of the following statements about a catalyst is incorrect?
A. It initiates the reaction.
B. It remains unchanged in mass after the reaction.
C. It does not change the enthalpy of the reaction.
D. It lowers the activation energy.
Answer: Option A
Solution (By JKSSB Mock Tests)
A catalyst does not initiate a reaction; it only changes the rate of a reaction that is already thermodynamically feasible. It provides an alternative pathway with lower activation energy. It does not change the overall enthalpy (ΔH) or the equilibrium position, and it is recovered unchanged in mass.
Explanation:
Azotobacter is a free-living aerobic bacterium that fixes atmospheric nitrogen in the soil, making it available to non-leguminous crops. Rhizobium is symbiotic and specific to legumes. Nitrobacter and Nitrosomonas are involved in nitrification (converting ammonia to nitrites/nitrates), not nitrogen fixation.
Explanation:
Liquefied Petroleum Gas (LPG) primarily consists of butane (C₄H₁₀) and isobutane, with some propane. For domestic use, it is often a mix of butane and propane. Methane is the main component of CNG and natural gas, which require different storage pressures and infrastructure.
Explanation:
Calcination involves heating an ore in limited supply or absence of air, often to convert carbonates/hydroxides to oxides and remove moisture or volatile impurities. Example: CaCO₃ → CaO + CO₂; Al(OH)₃ → Al₂O₃ + 3H₂O. Roasting is heating in excess air, usually for sulfide ores. Smelting uses reducing agents to obtain metal. Leaching uses chemicals.
No comments yet. Be the first to start the discussion!