Answer:
Observations
- The Polonium nucleus disintegrates to form a stable Lead nucleus with the emission of an alpha particle.
- The mass number of the original Polonium nucleus decreases by 4 ( ie from 210 to 206)
- The atomic number of the original Polonium nucleus decreases by 2 (ie from 84 to 82)
Explanation:
Polonium (Po) is a radioactive silver-grey material that exists in very low concentrations as a solid in the environment.
As a radioactive substance, it is unstable and then it undergoes radioactive alpha decay to form a stable chemical element - Lead (Pb)
Polonium Nucleus before decay
Polonium (²¹⁰₈₄Po) has a mass number of 210 and an atomic number of 84. The atomic number tells us that Polonium has 84 protons in its nucleus before it undergoes decay.
The mass number tell us that Polomium has 126 neutrons in addition to the 84 protons in its nucleus
The total number of protons and neutrons in a nucleus make up its Mass Number
Polonium Nucleus after decay
Polonium undergoes radioactive decay by emitting an alpha particle, which is also known as a Helium particle (⁴₂He)
²¹⁰ ₈₄Po ⇒ ²⁰⁶ ₈₂Pb + ⁴₂He
Observations
- The Polonium nucleus disintegrates to form a stable Lead nucleus with the emission of an alpha particle
- The mass number of the original Polonium nucleus reduces by 4 ( ie from 210 to 206)
- The atomic number of the original Polonium nucleus decreases by 2 (ie from 84 to 82)
- A new stable element (Lead) is formed.
- An alpha particle (⁴₂He) is released.
