Chapter 5, Problem 5.45UTC

Interpretation Introduction

To determine: The diagram of the new nucleus when the given isotope emits a positron

Answer to Problem 5.45UTC

Solution:

The new nucleus when the given isotopes emit a positron is as follows:

Explanation of Solution

Isotopes:

The atoms of an element with different mass number or atomic mass are called isotopes. They have same number of protons and electrons but different number of neutrons.

Therefore it in not necessary that all atoms of a given element contain the same number of neutrons in their nuclei . For example hydrogen has three isotopes ${\text{H}}^{\text{1}}{\text{, H}}^{\text{2}}{\text{,H}}^{\text{3}}$ with 0, 1 and 2 neutrons in their nuclei respectively.

Positron particle ( $\beta$ ) emission means that the new nucleus has the same mass number and 1 unit decrease in atomic number.

To balance the nuclear reaction as follows:

1. The sum of the subscript means the atomic numbers must be equal on the both side of the equation.
2. The sum of the superscript means the mass numbers must be equal on the both side of the equation.

Calculation:

When an atom of X-11 emits a positron then Y-11 is formed. The balanced nuclear reaction is as follows:

$\text{X}\to \text{Y}+e$

Conclusion

Therefore; the new nucleus when the given isotopes emit a positron; has same in mass number and 1 unit’s decreases in atomic number as follows: