what causes pressure changes of reactants to affect the reaction rate?\na. the speed of the molecules is…
what causes pressure changes of reactants to affect the reaction rate?\na. the speed of the molecules is changed.\nb. the boiling point of the gas is changed.\nc. the temperature of the molecules is changed.\nd. the frequency of collisions is changed.
Answer
Brief Explanations:
To determine the correct answer, we analyze each option:
- Option A: Changing pressure (for gases) doesn't directly change molecular speed; that's related to temperature (kinetic energy). So A is incorrect.
- Option B: Boiling point is a property of the substance and not related to reaction rate due to pressure changes. So B is incorrect.
- Option C: Pressure change (without temperature change) doesn't change the temperature of molecules. Temperature change affects kinetic energy, but pressure (volume change for gas) affects collision frequency. So C is incorrect.
- Option D: When pressure of reactant gases is changed (e.g., decreasing volume increases pressure), the molecules are closer together, so the frequency of collisions between reactant molecules increases, which affects the reaction rate. This matches the concept of how pressure affects reaction rate (for gaseous reactants).