Question

Complete the nuclear equation

218/84Po −→ 4/2He +? .
1. ? = 222/86Rn
2. ? = 222/86Pb
3. None of these
4. ? = 214/82Rn
5. ? = 214/82Pb
6. ? = 222/86Po
7. ? = 214/82Po

Answer 1

The complete nuclear equation for the alpha decay of Polonium-218 is 218/84Po → 4/2He + 214/82Pb. By subtracting the alpha particle's mass and atomic numbers from Polonium-218, Lead-214 is identified as the daughter isotope.

Step-by-step explanation:

The provided nuclear equation represents the alpha decay of Polonium-218 (Po-218). When a nucleus emits an alpha particle (4/2 He), it loses 2 protons and 2 neutrons. This decrease in mass and atomic numbers must be accounted for in the daughter isotope to balance the equation. Applying the conservation of mass and atomic numbers to the equation 218/84Po → 4/2He + ? we use subtraction to find the mass and atomic numbers of the daughter isotope:

• Subtract the mass number of the alpha particle (4) from the mass number of Po-218 (218), which gives us 214 (218 - 4 = 214).
• Subtract the atomic number of the alpha particle (2) from the atomic number of Po-218 (84), which gives us 82 (84 - 2 = 82).

Therefore, the missing term is 214/82Pb (Lead-214).

Answer to the equation: 218/84Po → 4/2He + 214/82Pb.

The correct option from the list provided by the student is:

5. ? = 214/82Pb

Answer 2

In order to solve this question, we must apply the conservation of mass. The total number of nucleons (upper number) and protons (lower number) must be equal before and after the decay. The new nucleon number is
218 - 4
= 214
And new proton number is
84 - 2
= 82
Next, we must identify which element has the proton number 82. That would be lead, Pb.
Therefore, the answer is
5. ²¹⁴Pb₈₂