In the long form of periodic table elements with low ionisation potential are present in

Options

A. I A group
B. IV B group
C. VII A group
D. I B group

Answer

To solve the question regarding where elements with low ionization potential are present in the long form of the periodic table, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Ionization Potential**:
- Ionization potential (or ionization energy) is the energy required to remove an electron from an atom. Elements with low ionization potential tend to lose electrons easily.

2. **Identify Groups in the Periodic Table**:
- The question provides four groups: 1A, 4B, 1B, and 7A. We need to analyze each group to determine where elements with low ionization potential are located.

3. **Analyze Group 1A (Alkali Metals)**:
- Group 1A consists of alkali metals such as Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), and Francium (Fr).
- Alkali metals have a single electron in their outermost shell, making it easy for them to lose that electron and achieve a stable noble gas configuration. Therefore, they have low ionization potentials.

4. **Analyze Group 4B (Carbon Family)**:
- Group 4B includes elements like Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn), and Lead (Pb).
- These elements have a higher number of valence electrons compared to alkali metals, which makes it more difficult to lose an electron. Hence, they generally have higher ionization potentials.

5. **Analyze Group 1B (Transition Metals)**:
- Group 1B consists of transition metals such as Copper (Cu), Silver (Ag), and Gold (Au).
- Transition metals typically have higher ionization energies due to their d-orbitals and the stability associated with their electron configurations.

6. **Analyze Group 7A (Halogens)**:
- Group 7A includes elements like Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At).
- Halogens have high ionization potentials because they are one electron short of a full outer shell and tend to gain electrons rather than lose them.

7. **Conclusion**:
- Based on the analysis, the group with elements that have low ionization potential is **1A (Alkali Metals)**.

### Final Answer:
Elements with low ionization potential are present in **Group 1A (Alkali Metals)**.

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