ANS:C - 1000-10000

In the catalytic cracking process, olefins crack 10 times faster than in the thermal cracking process. Here’s an explanation:

• Catalytic Cracking: Catalytic cracking is a refining process where high-molecular-weight hydrocarbons are broken down into lighter, more valuable products (such as gasoline and diesel) using a catalyst. The catalyst facilitates the cracking reaction at lower temperatures compared to thermal cracking.
• Olefins: Olefins, which are unsaturated hydrocarbons with at least one carbon-carbon double bond (e.g., ethylene, propylene), crack more rapidly in the presence of a catalyst. The catalytic action lowers the activation energy required for the cracking reaction, allowing olefins to break apart into smaller molecules more efficiently.
• Comparison with Thermal Cracking: In thermal cracking (without a catalyst), the cracking of olefins occurs more slowly because it relies solely on high temperatures to break chemical bonds. The absence of a catalyst means that the cracking reactions are less selective and require higher temperatures to achieve comparable rates of cracking.