Question

Determine the value of the rate constants for the elementary reaction.I2(g)+2HI(aq) give that when [I2]is 0.15M and [H2]is the rate of reaction is 0.005Ms-1at 298 k

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Answer 1

Given info : the elementary reaction: I₂ (g)+H₂ (g)→2HI (aq)

Where [I₂] is 0.15 M and [H₂] is 0.2M, the rate of reaction is 0.005 M s⁻¹ at 298 K.

To find : value of rate constant for the given reaction.

solution : we can write , rate of reaction, r = k[I₂][H₂]

Here given, r = 0.005 Ms¯¹ , [I₂] = 0.15M , [H₂] = 0.2M

so, 0.005 Ms¯¹= k × 0.15 M × 0.2 M

⇒0.005 = k × 0.03

⇒k = 0.5/3 = 0.166 M¯¹s¯¹

Therefore the rate constant of given reaction is 0.166 M¯¹s¯¹.