For a zero-order reaction, if the initial concentration is 0.5 M and the rate co
Practice Questions
Q1
For a zero-order reaction, if the initial concentration is 0.5 M and the rate constant is 0.1 M/s, how long will it take for the concentration to drop to 0.2 M?
3 s
5 s
7 s
10 s
Questions & Step-by-Step Solutions
For a zero-order reaction, if the initial concentration is 0.5 M and the rate constant is 0.1 M/s, how long will it take for the concentration to drop to 0.2 M?
Step 1: Identify the initial concentration of the reactant, which is [A]0 = 0.5 M.
Step 2: Identify the final concentration of the reactant, which is [A] = 0.2 M.
Step 3: Identify the rate constant, which is k = 0.1 M/s.
Step 4: Write the formula for a zero-order reaction: [A] = [A]0 - kt.
Step 5: Substitute the known values into the formula: 0.2 M = 0.5 M - (0.1 M/s)t.
Step 6: Rearrange the equation to solve for t: (0.1 M/s)t = 0.5 M - 0.2 M.
Step 7: Calculate the difference: 0.5 M - 0.2 M = 0.3 M.
Step 8: Now the equation is (0.1 M/s)t = 0.3 M.
Step 9: Divide both sides by 0.1 M/s to find t: t = 0.3 M / 0.1 M/s.
Step 10: Calculate t: t = 3 seconds.
Zero-Order Reactions – In zero-order reactions, the rate of reaction is constant and independent of the concentration of the reactant.
Rate Law – The rate law for a zero-order reaction is expressed as [A] = [A]0 - kt, where [A]0 is the initial concentration, k is the rate constant, and t is time.
