A sample of radioactive material has mass m, decay constant lambda, and molecular weight M. Avogadro constant =N_(A). The initial activity of the sample is:

A sample of radioactive material has mass m, decay constant lambda, an

1.	A sample of radioactive material has mass m, decay constant lambda, and molecular weight M. Avogadro constant =N_(A). The initial activity of the sample is:
Answer» `LAMBDAM` `(lambdam)/M` `(lambdamN_A)/M` `mN_Alambda` Solution :Activity = number of disintegrations per unit TIME Activity =`\|(dN)/(dt)\|=lambdaN` where N = the TOTAL number of nuclei ALSO, N = number of MOLES x `N_A=(m/M)N_A` `therefore ` Initial activity=`(lambda mN_A)/M`

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A sample of radioactive material has mass m, decay constant lambda, and molecular weight M. Avogadro constant =N_(A). The initial activity of the sample is:

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