When radium atom which is placed in II group, loses an `alpha`- particle, a new element is formed which should be placed in group?

Options

A. Second
B. First
C. Fourth
D. Zero

Answer

To solve the question, we need to determine the group placement of the new element formed when a radium atom loses an alpha particle. Let's break down the steps:

### Step-by-Step Solution:

1. **Identify the Initial Element**:
- The initial element is radium (Ra), which is in Group 2 of the periodic table.

2. **Understand Alpha Decay**:
- An alpha particle consists of 2 protons and 2 neutrons, which means it has a mass number of 4 and an atomic number of 2.
- When an atom undergoes alpha decay, it loses this alpha particle.

3. **Calculate the New Atomic Number and Mass Number**:
- The mass number of radium (Ra) is 226 (for example, Ra-226).
- After losing an alpha particle, the new mass number will be:
\[ 226 - 4 = 222 \]
- The atomic number of radium is 88. After losing 2 protons (due to the alpha particle), the new atomic number will be:
\[ 88 - 2 = 86 \]

4. **Identify the New Element**:
- The element with atomic number 86 is radon (Rn).

5. **Determine the Group of the New Element**:
- Radon (Rn) is located in Group 18 of the periodic table, which is also known as the noble gases or zero group.

### Final Answer:
The new element formed after radium loses an alpha particle is placed in Group 18 (or zero group) of the periodic table.

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