Question bank/NEET UG/Chemistry

NEET UGChemistryModerateNEET 2025

If the half-life (t1/2_{1/2}) for a first order reaction is 1 minute, then the time required for 99.9% completion of the reaction is closest to :

Show answer and solution
For 1st^{st} order reaction
kt = 2.303 log
A0At\frac{A_{0}}{A_{t}} A0_{0} = initial concentration
A
t_{t} = Final concentration
t
99.9%=10_{99.9\%} = 10 t1/2_{1/2}
t
99.9%=10×1_{99.9\%} = 10 \times 1 minute = 10 minutes

Source: geekyrakshit/indian-exam-questions / neet2025-code45

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