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Question
A first order reaction is 50% complete in 25 minutes. Calculate the time for 80% completion of the reaction.
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Solution
`t_{1//2} = 25 ` minutes ⇒k = `0.693 /{25 "mins"}`
K = `2.303/25 = 2.303/tlog 100/{a_1} `
⇒ `0.693/25 = 2.303/t log 100/20` 80% completion
`t = 2.303/0.693 xx 25 xx 0.6990`
t = 57.3 mins
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