Chapter 17, Problem 47A

To determine

The resultant element.

Answer to Problem 47A

The element that results if two protons and two neutrons are ejected from a uranium nucleus is thorium.

Explanation of Solution

Introduction:

Uranium is one of the naturally available radioactive element. It can be used to produce useful energy. Chemical symbol of uranium is $\text{U}$ and its atomic number is $\text{92}$ . In the isotopes of uranium, $\text{U-238}$ is the most stable.

The ejection of two protons and two neutrons from a uranium nucleus leads to the formation of an atom with atomic number $\text{90}$ and mass number $\text{234}$ . The element with atomic number $\text{90}$ and mass number $\text{234}$ is the $\text{thorium - }234$ . This is the radioactive isotope of $\text{thorium - }232$ . Chemical symbol of thorium is $Th$ .