Question

Identify the pair of elements with the highest and lowest electronegativity respectively

• A. K and Rb
• B. I and F
• C. F and Fr
• D. Fr and Li

Hint:

Fluorine has the highest electronegativity, while Francium has the lowest.

Answer 1

The Correct Option is C

Electronegativity refers to the ability of an atom to attract shared electrons in a chemical bond.
- Fluorine (F) is the most electronegative element in the periodic table, with a high electronegativity value.
- Francium (Fr) has the lowest electronegativity value due to its large atomic size and low effective nuclear charge.
Thus, the pair of elements with the highest and lowest electronegativity respectively is \( \boxed{F \text{ and } Fr} \).

Answer 2

Step 1: Understand the concept of electronegativity.
Electronegativity is the tendency of an atom to attract shared electrons in a chemical bond.
It generally increases across a period (left to right) and decreases down a group (top to bottom) in the periodic table.

Step 2: Identify the element with the highest electronegativity.
- Fluorine (F) is the most electronegative element with a value of approximately 3.98 on the Pauling scale.

Step 3: Identify the element with the lowest electronegativity.
- Francium (Fr), an alkali metal at the bottom of Group 1, has the lowest electronegativity (estimated around 0.7).

Step 4: Conclusion.
The pair of elements with the highest and lowest electronegativity are Fluorine (F) and Francium (Fr) respectively.
Hence, the correct answer is: F and Fr.