Given the following nuclear reaction:

Question

224/88 Ra - 4/2 He + A/Z X
Column A
1.
What is the atomic mass of the new atom?
2.
What is the atomic number of the new atom?
3.
What is the symbol of the new atom?
4.
What type of decay is demonstrated here?
Column B
a. 84
b. 224
c. 220
d. Rn
e. 90
f. Beta Decay
g. 86
h. 88
i. Th
j. Alpha Decay
k. Gamma Decay
l. 228
m. Ra

Answer 1

To analyze the nuclear reaction:

\[ \frac{224}{88} \text{Ra} \rightarrow \frac{4}{2} \text{He} + \frac{A}{Z} \text{X} \]

1. What is the atomic mass of the new atom?

   • The original atom has a mass number of 224 and the He nucleus (alpha particle) has a mass number of 4. Therefore: \[ A = 224 - 4 = 220 \]
   • So, the atomic mass of the new atom is 220.

2. What is the atomic number of the new atom?

   • The atomic number of radium (Ra) is 88 and the atomic number of helium (He) is 2. Therefore: \[ Z = 88 - 2 = 86 \]
   • So, the atomic number of the new atom is 86.

3. What is the symbol of the new atom?

   • The element with atomic number 86 is radon (Rn). So the symbol of the new atom is Rn.

4. What type of decay is demonstrated here?

   • Since radium is emitting an alpha particle (He nucleus), the type of decay occurring is Alpha Decay.

Column A Answers:

1. Atomic mass of the new atom: 220 (c)
2. Atomic number of the new atom: 86 (g)
3. Symbol of the new atom: Rn (d)
4. Type of decay: Alpha Decay (j)

Summary of Answers:

• 1: c (220)
• 2: g (86)
• 3: d (Rn)
• 4: j (Alpha Decay)