Ionic bonds generally form when the bonded elements have a difference in electronegativity greater than 1.5 to 1.7. subtract the electronegativities for the following pairs of elements and predict whether they form ionic bonds.

electronegativity difference of na and f:  

yes

no

Yes

Explanation:

Electronegativity value of Flourine (F)  = 3.98

Electronegativity value of Sodium (Na) = 0.93

Electronegativity difference = 3.98 - 0.93 = 3.05

Since the electronegativity difference is greater than 1.5, it means the bond formed would be an ionic bond.

i just got this problem. it's 90.3

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