Chapter 39, Problem 65A

To determine

Proof that target material contain nitrogen-13.

Explanation of Solution

Introduction:

The atomic number of the element decreases by two units and atomic mass number by four units due to decay of one alpha particle.

The atomic number of oxygen-16 atom is 8 and atomic mass number 16. It consist 8 protons and 8 neutrons in the nucleus.

One proton is bombarded on the oxygen-16. So, the total proton in the nucleus becomes 9 and atomic mass become 17.

If one alpha particle decays from the oxygen-16 atom, then the remaining number of proton in the nucleus of new element becomes 7 and atomic mass number of new element becomes 13.

The expression for the decay of oxygen-16 atom by bombard of one proton and one alpha particle.

${}_8^{16}\text{O}{+}_1^1\text{H}{\to }_7^{13}\text{N}{+}_2^4\text{He}$

The number of protons in the nucleus of Nitrogen is also 7. So, the new element is Nitrogen and target material contains Nitrogen-13.

Conclusion:

Thus, the target material contains Nitrogen-13, because the number of protons in the nucleus of new element is 7 and number of neutrons is 6.