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Hi, in this question we are having radium 226 isotope.
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The half -life is given as 1600 years.
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The mass of sample radium 226 is 6 .9 milligram.
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We are asked to calculate the activity in units of bequerels and curie.
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We know that activity is represented by a symbol q.
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It is equal to lambda n, where lambda is the decay constant.
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And n represents the total number of atoms in one gram.
00:44
First of all, we will calculate the decay constant lambda.
00:48
It is equal to 0 .693 divided by t -half.
00:54
We can substitute the values.
00:56
Here, we are having 0 .693 value divided by t -half, which is 5 .04.
01:04
5 into 10 raise to power 10 second.
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On calculation we will get the lambda value equals to 1 .37 into 10 raise to power minus 11 per second.
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Now we will calculate the n value that is total number of atoms present in 1 gram.
01:24
It is equal to moles into evergadro number.
01:30
We know that moles are equal to divided by molar mass.
01:37
Here we are having atom therefore we will take the atomic mass...