Chapter 4, Problem 95A

Interpretation Introduction

Interpretation:

Atomic nucleus contains 92 protons and the mass number is 235. The number of neutrons and name of the atom needs to be determined.

Concept introduction:

The number of protons present in the nucleus represents the atomic number of the element. The neutron and protons present together in the nucleus and the number of electron is equal to the number of protons.

Answer to Problem 95A

The number of neutron is 143. And the atom is Uranium.

Explanation of Solution

For any element-

$\begin{array}{l}Atomicnumber=Numberofprotons\hfill \\ Numberofprotons\text{ = }Numberofelectrons\hfill \end{array}$

$Massnumber=numberofproton+numberofneutrons$

$Numberofneutrons=atomicmass-atomicnumber$

$Theatomicnumber=Numberofprotons$

$Thenumberofneutrons=235-92=143$

The atom is Uranium with atomic number 92 and mass number 235.

Conclusion

There are 143 neutrons in the atom of Uranium.