Question

In another process in which 235 92U undergoes neutron bombardment, the following reaction occurs: 235 92U+10n→AZSr+143 54Xe+310n Enter the isotope symbol for the strontium (Sr) nucleus in this reaction. Express your answer as an isotope.
17)Calculate the mass defect of the oxygen nucleus 16 8O. The mass of neutral 16 8O is equal to 15.994914 atomic mass units. Express your answer in atomic mass units to four significant figures.

Answer 1

Answer:

$_{38}^{90}\textrm{Sr}$

Mass defect of the oxygen nucleus is:- 0.1370 amu

Explanation:

In a nuclear reaction, the total mass and total atomic number remains the same.

For the given fission reaction:

$^{235}_{92}\textrm{U}+^1_0\textrm{n}\rightarrow ^A_Z\textrm{Sr}+^{143}_{54}\textrm{Xe}+3^1_0\textrm{n}$

To calculate A:

Total mass on reactant side = total mass on product side

235 + 1  = A + 143 + 3

A = 90

To calculate Z:

Total atomic number on reactant side = total atomic number on product side

92 + 0  = Z + 54 + 0

Z = 38

Hence, the isotopic symbol of strontium is:- $_{38}^{90}\textrm{Sr}$

The element given is:- $_{8}^{16}\textrm{O}$

Atomic number : It is defined as the number of electrons or number of protons present in a neutral atom.

Also, atomic number of O = 8

Thus, the number of protons = 8

Mass number is the number of the entities present in the nucleus which is the equal to the sum of the number of protons and electrons.

Mass number = Number of protons + Number of neutrons

16 =  8 + Number of neutrons

Number of neutrons = 8

Mass of neutron = 1.008665 amu

Mass of proton = 1.007825 amu

Calculated mass = Number of protons*Mass of proton + Number of neutrons*Mass of neutron

Thus,  

Calculated mass = (8*1.007825 + 8*1.008665) amu = 16.13192 amu

Given, mass of the atom = 15.994914 amu

Mass defect = Δm = |16.13192 - 15.994914| amu = 0.137006 amu

Mass defect of the oxygen nucleus is:- 0.1370 amu