general chemistry II

Question

Using the data in the table, calculate the rate constant of this reaction.

A+B⟶C+DA+B⟶C+D

Trial[𝐀] (𝐌)[A] (M)[𝐁] (𝐌)[B] (M)Rate (M/s)
1	0.2000.200	0.2500.250	0.02340.0234
2	0.2000.200	0.6250.625	0.1460.146
3	0.3000.300	0.2500.250	0.03510.0351

Answer 1

We assume r = kAⁿB^m

Now compare the ratios r₂/r₁ = (B₂/B₁)^m and solve for m

.1460/.0234 = (.625/.250)ⁿ or 6.293 = (2.5)^m which makes m approximately 2 by inspection. If you use logarithms you get m = ln(6.293)/ln(2.5) = 2.007

Do same comparison for r₃/r₁ = (A₂/A₁)ⁿ

.0351/.0234 = (.3/.2)ⁿ or 1.5 = (1.5)ⁿ so n = 1.000

Now just solve k = r/(A¹B²) for any of the 2 rows. You can check it with another row and get the same k.

Please consider a tutor. Take care.