A first order reaction takes 20 minutes for 25% decomposition. Calculate the time when 75% of the reaction will be completed?
(Given: Log 2 = 0.3010, Log 3 = 0.4771, Log 4 = 0.6021)
For the first order reaction
k = (2.303 / t) log (a / a – x)
When x = (25 / 100) a = 0.25 a
t = 20 minutes (given)
Therefore, k = (2.303 / 20) log (a / a – 0.25 a)
k = (2.303 / 20) log (1 / 0.75)
= 0.013120 min-1
Hence the value of the rate constant is 0.013120 min-1
Now we need to find Time for rest 75% reaction t= ?, when x = 0.75 a
From above, k = 0.013120 min-1
Therefore, t = (2.303 / 0.013120) log (a / a – 0.75 a)
= (2.303 / 0.013120 ) log (1 / 0.25 )
= 105.6 min.
The time at which the reaction will be 75% complete is 105.6 min.
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(i) Propene to propan-1-ol
(ii) Ethanol to but-1-yne
(iii) 1-Bromopropane to 2-bromopropane
(iv) Toluene to benzyl alcohol
(v) Benzene to 4-bromonitrobenzene
(vi) Benzyl alcohol to 2-phenylethanoic acid
(vii) Ethanol to propanenitrile
(viii) Aniline to chlorobenzene
(ix) 2-Chlorobutane to 3, 4-dimethylhexane
(x) 2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi) Ethyl chloride to propanoic acid
(xii) But-1-ene to n-butyliodide
(xiii) 2-Chloropropane to 1-propanol
(xiv) Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi) 2-Bromopropane to 1-bromopropane
(xvii) Chloroethane to butane
(xviii) Benzene to diphenyl
(xix) tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide
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SO2Cl2(g) → SO2(g) + Cl2(g)
Experiment |
Time/s - 1 |
Total pressure/atm |
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