Question

two solid reactants of varying particle size are combined in a vessel. assuming that the same mass of each reactant is used in each case, which of the following represents the conditions that will result in the fastest reaction rate?
a
temperature = 950° c

b
temperature = 500° c

c
temperature = 500° c

d
temperature = 950° c

Explanation:

Step1: Recall reaction rate factors

Reaction rate for solids depends on particle size (surface area) and temperature. Smaller particles have larger surface area, and higher temperature increases rate.

Step2: Analyze particle size

Options C and D have smaller particles (more surface area) than A and B (larger particles).

Step3: Analyze temperature

Among C (500°C) and D (950°C), D has higher temperature. Higher temp + larger surface area (small particles) gives fastest rate.

Step4: Identify the option

Option D has small particles (from the diagram, D's particles are smaller) and 950°C, so it has both large surface area and high temperature.

Answer:

D. Temperature = 950° C (with small particle size as per the diagram)