Which of the following is the correct explanation regarding s block elements?

Options

A. they are soft metals with high melting point and boiling point
B. they have high ionisation enthalpy
C. they are strong oxidising agent
D. they are good conductor of electricity and heat

Answer

To determine the correct explanation regarding s-block elements, we can analyze the properties and characteristics of these elements step by step.

### Step-by-Step Solution:

1. **Location in the Periodic Table**:
- S-block elements are located in Group 1 (alkali metals) and Group 2 (alkaline earth metals) of the periodic table.
- Examples include lithium (Li), sodium (Na), potassium (K), beryllium (Be), and magnesium (Mg).

**Hint**: Remember the groups where s-block elements are found.

2. **Nature of S-block Elements**:
- All s-block elements are metals. They exhibit metallic properties such as luster, malleability, and ductility.
- They can be categorized into soft (like sodium and potassium) and hard (like beryllium and magnesium) metals.

**Hint**: Identify the characteristics that define metals.

3. **Ionization Enthalpy**:
- S-block metals have relatively low ionization enthalpy, which means they require less energy to lose their outermost electrons.
- This is because they have a single electron in their outermost shell (for Group 1) or two electrons (for Group 2), making it easier to lose these electrons.

**Hint**: Consider how the number of valence electrons affects ionization energy.

4. **Oxidizing and Reducing Agents**:
- S-block elements are generally good reducing agents. This means they tend to lose electrons easily and can oxidize other substances.
- They do not act as strong oxidizing agents; rather, they facilitate reduction in other species by donating electrons.

**Hint**: Recall the definitions of oxidizing and reducing agents.

5. **Electrical and Thermal Conductivity**:
- S-block metals are good conductors of electricity and heat due to the presence of free-moving electrons in their metallic structure.
- This property is typical of metals, allowing them to conduct energy efficiently.

**Hint**: Think about the role of free electrons in conductivity.

### Conclusion:
The correct explanation regarding s-block elements includes their location in the periodic table, their metallic nature, low ionization enthalpy, their role as reducing agents, and their ability to conduct electricity and heat.