Which pair of atoms has the highest electronegativity difference?

\begin{tabular}{|c|c|}
\hline
Elements & Electronegativity \\
\hline
calcium [tex]$(Ca)$[/tex] & 1.0 \\
\hline
carbon [tex]$(C)$[/tex] & 2.55 \\
\hline
fluorine [tex]$(F)$[/tex] & 4.0 \\
\hline
hydrogen [tex]$(H)$[/tex] & 2.2 \\
\hline
phosphorus [tex]$(P)$[/tex] & 2.19 \\
\hline
sodium [tex]$(Na)$[/tex] & 0.93 \\
\hline
\end{tabular}

A. [tex]$Na - F$[/tex]
B. [tex]$Ca - F$[/tex]
C. [tex]$H - F$[/tex]
D. [tex]$C - F$[/tex]
E. [tex]$F - F$[/tex]



Answer :

To determine which pair of atoms has the highest electronegativity difference, we first need to calculate the absolute differences in electronegativity for each pair listed.

Given the electronegativity values:
- Calcium (Ca) = 1.0
- Carbon (C) = 2.55
- Fluorine (F) = 4.0
- Hydrogen (H) = 2.2
- Phosphorus (P) = 2.19
- Sodium (Na) = 0.93

Let's compute the electronegativity differences for each specified pair:

1. Na and F:
[tex]\[ |\chi_{\text{Na}} - \chi_{\text{F}}| = |0.93 - 4.0| = 3.07 \][/tex]

2. Ca and F:
[tex]\[ |\chi_{\text{Ca}} - \chi_{\text{F}}| = |1.0 - 4.0| = 3.0 \][/tex]

3. H and F:
[tex]\[ |\chi_{\text{H}} - \chi_{\text{F}}| = |2.2 - 4.0| = 1.8 \][/tex]

4. C and F:
[tex]\[ |\chi_{\text{C}} - \chi_{\text{F}}| = |2.55 - 4.0| = 1.45 \][/tex]

5. F and F (this would always be zero since it's the same element):
[tex]\[ |\chi_{\text{F}} - \chi_{\text{F}}| = |4.0 - 4.0| = 0.0 \][/tex]

Now, let's compare the absolute differences:

- Na - F: 3.07
- Ca - F: 3.0
- H - F: 1.8
- C - F: 1.45
- F - F: 0.0

Among these, the highest electronegativity difference is clearly between sodium (Na) and fluorine (F), with a difference of 3.07.

Thus, the pair of atoms with the highest electronegativity difference is:

[tex]\[ \boxed{Na - F} \][/tex]