NEETChemistryChemical Kinetics
For a zero-order reaction, a plot of half-life ( t_ 1/2 ) on the y-axis versus the initial concentration ( [ A ]₀ ) on the x-axis yields a straight line passing through the origin. If the slope of this line is 50 L mol ⁻¹ s , the rate constant for the reaction is:
Options
- A50 mol L ⁻¹ s ⁻¹
- B1.0 10⁻² mol L ⁻¹ s ⁻¹
- C2.0 10⁻² mol L ⁻¹ s ⁻¹
- D1.0 10² mol L ⁻¹ s ⁻¹
Correct answer
B. 1.0 10⁻² mol L ⁻¹ s ⁻¹
Step-by-step solution
For a zero-order reaction, the relationship between half-life and initial concentration is given by: t_ 1/2 = [ A ]₀ 2k Comparing this with the equation of a straight line passing through the origin ( y = mx ), the slope ( m ) is: m = 1 2k Given that the slope m = 50 L mol ⁻¹ s , we can solve for the rate constant k : k = 1 2m = 1 2 50 = 1 100 = 1.0 10⁻² mol L ⁻¹ s ⁻¹ Answer: 1.0 10⁻² mol L ⁻¹ s ⁻¹