t1/2=15 minutes ∴ No. of half lives s=2 ( ∴ for change of 0.1 to 0.025 ) is 30 minutes
In first order reaction, the concentration of the reactant decreases from 0.8M to 0.4M in 15 minutes. The time taken for the concentration to change from 0.1M to 0.025M is
Held on 30 Apr 2004 · Verified 6 Jul 2026.
30 minutes
60 minutes
7.5 minutes
15 minutes
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The ratio of mass percentage (w/w) of C : H in a hydrocarbon is $12 : 1$. It has two carbon atoms. The weight (in g) of $CO_2(g)$ formed when $3.38$ g of this hydrocarbon is completely burnt in oxygen is : (Given : Molar mass in g mol$^{-1}$ C : 12, H : 1, O : 16)
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