﻿ The half-life of thorium-X is 3.64 days. After how many days will 0.1 of the mass of a sample of the substance remain undecayed? : Kaysons Education

# The Half-life Of Thorium-X is 3.64 Days. After How Many Days Will 0.1 Of The Mass Of A Sample Of The Substance Remain undecayed?

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## Question

### Solution

Correct option is

12.1 days

The decay constant is

= 0.1904 per day.

If initially (at time t = 0), the number of atoms in a radioactive element beN0 and the number of atoms left at time t be N, then

= 12.1 days.

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