How many α and β – particles are emitted in the trasmutation\(_{90

1.	How many α and β – particles are emitted in the trasmutation\(_{90}^{232}Th\) → \(_{82}^{208}Pb\)
Answer» \(_{90}^{232}Th\) → \(_{82}^{208}Pb\) The emission of one α-particle decreases the mass number by 4 whereas the emission of βparticles has no effect on mass number. Net decrease in mass number = 232 – 208 = 24. This decrease is only due to α-particles. Hence, Number of α-particles emitted = \(\frac{24}{4}\) = 6 Now, The emission of one α-particle decrease the atomic number by 2 and one β-particle emission increases it by 1. The net decrease in atomic number = 90 – 82 = 8 The emission of 6 α-particles causes decrease in atomic number by 12. However, The actual decrease is only 8. Thus, Atomic number increases by 4. This increase is due to emission of 4 β-particles. Thus, 6 α and 4 β-particles are emitted.

How many α and β – particles are emitted in the trasmutation\(_{90}^{232}Th\) → \(_{82}^{208}Pb\)

Answer»

\(_{90}^{232}Th\) → \(_{82}^{208}Pb\)

The emission of one α-particle decreases the mass number by 4 whereas the emission of βparticles has no effect on mass number.

Net decrease in mass number = 232 – 208 = 24.

This decrease is only due to α-particles.

Hence,

Number of α-particles emitted = \(\frac{24}{4}\) = 6

Now,

The emission of one α-particle decrease the atomic number by 2 and one β-particle emission increases it by 1.

The net decrease in atomic number = 90 – 82 = 8

The emission of 6 α-particles causes decrease in atomic number by 12.

However,

The actual decrease is only 8.

Thus,

Atomic number increases by 4.

This increase is due to emission of 4 β-particles.

Thus,

6 α and 4 β-particles are emitted.