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missylulu
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hi. a firstorder reaction has a half life of 26.4 seconds. how long will it take for the concentration of the reactant in the reaction to fall to 1/8 of its initial value? please help me omg
 one year ago
 one year ago
missylulu Group Title
hi. a firstorder reaction has a half life of 26.4 seconds. how long will it take for the concentration of the reactant in the reaction to fall to 1/8 of its initial value? please help me omg
 one year ago
 one year ago

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miley28 Group TitleBest ResponseYou've already chosen the best response.0
i'll give u an easy formula for this.. time taken for conc. of reactant to fall is, n*half life=initial conc/\[2^{n}\]
 one year ago

miley28 Group TitleBest ResponseYou've already chosen the best response.0
since here it is given 1/8 of its initial value so accordin to the formula, 3*26.4=initial conc/\[2^{3}\] thus time taken is=3*26.4=79.2secs
 one year ago

miley28 Group TitleBest ResponseYou've already chosen the best response.0
but remember this formula is only applicable for 1st order reactions... or elase u may apply the general rate constant formulas.
 one year ago

aaronq Group TitleBest ResponseYou've already chosen the best response.1
first order reaction so use: \[t _{1/2}=\frac{ \ln2 }{ k }\] find k then, use: \[A=A _{0}e ^{kt}\] assume Ao= initial = 1 then A = 1/8 solve for t, time, which will be in seconds
 one year ago

missylulu Group TitleBest ResponseYou've already chosen the best response.0
what formula is A = Ao e^kt ??
 one year ago

aaronq Group TitleBest ResponseYou've already chosen the best response.1
general equation for exponential decay or growth
 one year ago

missylulu Group TitleBest ResponseYou've already chosen the best response.0
oh that's right gahh sorry LOL
 one year ago
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