Question

polonium has a mass number of 212 and an atomic number of 84. in a balanced nuclear reaction, polonium releases an alpha particle to produce lead. which option is the atomic number of lead? (1 point) 208 82 210 80

Explanation:

Step1: Recall alpha - particle composition

An alpha - particle has 2 protons and 2 neutrons, so its atomic number is 2.

Step2: Calculate lead's atomic number

In a nuclear reaction, the atomic number is conserved. Polonium has an atomic number of 84. When it emits an alpha - particle, we subtract the atomic number of the alpha - particle from polonium's atomic number. So, $84−2 = 82$.

Answer:

B. 82