A first order reaction is 20% complete in 20 minutes. Calculate the time taken for the reaction to go to 80% completion.

Explanation

To solve the problem of determining the time taken for a first-order reaction to go from 20% completion to 80% completion, we can follow these steps:

### Step 1: Understand the Reaction Completion
Given that the reaction is 20% complete in 20 minutes, we can denote:
- Initial concentration = A
- Amount reacted (x) at 20% completion = 0.20A
- Remaining concentration at this point = A - x = A - 0.20A = 0.80A

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