Which of the following is most electronegative element.

Options

A. `Li`
B. `Mg`
C. `H`
D. `Na`

Answer

To determine which of the given elements is the most electronegative, we can follow these steps:

### Step 1: Understand Electronegativity Trends
- Electronegativity is the tendency of an atom to attract electrons in a chemical bond.
- As we move down a group in the periodic table, electronegativity decreases. This is due to the increase in atomic size and the shielding effect, which makes it harder for the nucleus to attract bonding electrons.
- As we move across a period from left to right, electronegativity increases. This is because the number of protons increases, which enhances the positive charge of the nucleus and its ability to attract electrons.

### Step 2: Analyze the Given Options
- Let's assume the options given are: Hydrogen (H), Lithium (Li), Magnesium (Mg), and Sodium (Na).
- We will analyze the position of each of these elements in the periodic table:
- Hydrogen is in Group 1, Period 1.
- Lithium is in Group 1, Period 2.
- Sodium is in Group 1, Period 3.
- Magnesium is in Group 2, Period 3.

### Step 3: Apply the Trends to the Options
- According to the trend, Hydrogen, being the highest in the group and period, will have the highest electronegativity.
- Lithium, being below Hydrogen in the same group, will have a lower electronegativity than Hydrogen.
- Sodium, being further down in the same group as Lithium, will have an even lower electronegativity.
- Magnesium, being in Group 2 and Period 3, will also have a lower electronegativity than Hydrogen.

### Step 4: Conclusion
- From our analysis, we can conclude that Hydrogen (H) is the most electronegative element among the options provided.

### Final Answer
- The most electronegative element is **Hydrogen (H)**.

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