Give reasons in one or two sentences for the following: The mixture of hydrazine and hydrogen peroxides with a copper `(II)` catalyst is used as a rocket propellant.

Answer

**Step-by-Step Solution:**

1. **Understanding Rocket Propellant:**
- A rocket propellant is a substance that produces thrust when it undergoes a chemical reaction. It is essential for propelling rockets into space.

2. **Chemical Reaction Involved:**
- The mixture of hydrazine (N2H4) and hydrogen peroxide (H2O2) undergoes a reaction in the presence of a copper (II) catalyst. This reaction is exothermic, meaning it releases a significant amount of heat.

3. **Products of the Reaction:**
- The reaction produces nitrogen gas (N2) and water (H2O) as the main products. The release of nitrogen gas contributes to the thrust needed for rocket propulsion.

4. **Exothermic Nature of the Reaction:**
- The exothermic nature of the reaction means that it releases energy in the form of heat, which can be converted into kinetic energy, providing the necessary thrust for the rocket.

5. **Role of the Copper (II) Catalyst:**
- The copper (II) catalyst facilitates the reaction between hydrazine and hydrogen peroxide, increasing the reaction rate and ensuring that the propellant burns efficiently.

**Final Reason:**
The mixture of hydrazine and hydrogen peroxide with a copper (II) catalyst is used as a rocket propellant because it undergoes an exothermic reaction that produces nitrogen gas and water, releasing a large amount of energy that generates thrust.

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