Respuesta :

That will make a gold-202 nucleus.

Explanation

Refer to a periodic table. The atomic number of mercury Hg is 80.

Step One: Bombard the [tex]\displaystyle ^{202}_{\phantom{2}80}\text{Hg}[/tex] with a neutron [tex]^{1}_{0}n[/tex]. The neutron will add 1 to the mass number 202 of [tex]^{202}_{\phantom{2}80}\text{Hg}[/tex]. However, the atomic number will stay the same.

  • New mass number: 202 + 1 = 203.
  • Atomic number is still 80.

[tex]^{202}_{\phantom{2}80}\text{Hg} + ^{1}_{0}n \to ^{203}_{\phantom{2}80}\text{Hg}[/tex].

Double check the equation:

  • Sum of mass number on the left-hand side = 202 + 1 = 203 = Sum of mass number on the right-hand side.
  • Sum of atomic number on the left-hand side = 80 = Sum of atomic number on the right-hand side.

Step Two: The [tex]^{203}_{\phantom{2}80}\text{Hg}[/tex] nucleus loses a proton [tex]^{1}_{1}p[/tex]. Both the mass number 203 and the atomic number will decrease by 1.

  • New mass number: 203 - 1 = 202.
  • New atomic number: 80 - 1 = 79.

Refer to a periodic table. What's the element with atomic number 79? Gold Au.

[tex]^{203}_{\phantom{2}80}\text{Hg} \to ^{202}_{\phantom{2}79}\text{Au} + ^{1}_{1}p[/tex].

Double check the equation:

  • Sum of mass number on the left-hand side = 203 = 202 + 1 = Sum of mass number on the right-hand side.
  • Sum of atomic number on the left-hand side = 80 = 79 + 1 = Sum of atomic number on the right-hand side.

A gold-202 nucleus is formed.