consider the reaction below. c2h4(g) + h2(g) → c2h6(g) which change would likely cause the greatest increase…

consider the reaction below. c2h4(g) + h2(g) → c2h6(g) which change would likely cause the greatest increase in the rate of the reaction? decrease temperature and decrease pressure increase temperature and decrease pressure decrease temperature and increase pressure increase temperature and increase pressure

consider the reaction below. c2h4(g) + h2(g) → c2h6(g) which change would likely cause the greatest increase in the rate of the reaction? decrease temperature and decrease pressure increase temperature and decrease pressure decrease temperature and increase pressure increase temperature and increase pressure

Answer

Answer:

D. increase temperature and increase pressure

Explanation:

Step1: Effect of temperature on reaction rate

Increasing temperature provides more kinetic - energy to reactant molecules. This leads to more frequent and energetic collisions, increasing the reaction rate. Decreasing temperature has the opposite effect.

Step2: Effect of pressure on reaction rate

For gas - phase reactions like the given one ($C_2H_4(g)+H_2(g)\rightarrow C_2H_6(g)$), increasing pressure increases the concentration of reactant gases. Higher concentration means more reactant molecules per unit volume, resulting in more frequent collisions and an increased reaction rate. Decreasing pressure decreases the concentration and the reaction rate. So, to increase the rate of the reaction, we should increase both temperature and pressure.