Sodium Iodide. Can anyone help?

[Davespecifico]

Have just spent ages googling multiple combinations of key words and found nothing. Can anyone help? See pic.

Where is this question from/what is it for?

It’s year 9 Chemistry Homework.

Assuming this is GCSE level chemistry, it'll be something like explaining sodium has one electron in its outer shell but is more stable without it as Na+, iodine is more stable with an extra electron as I- (+ and - should be superscript) so they form an ionic bond with Na giving an electron to I.

Look up ionic bonding - NaCl would be the usual example.

They need to recognise that iodine is in the same Group as chlorine, fluorine, and bromine so forms iodide in the same way.

Thanks jackparlabane. I’ve looked a lot at ionic bonding, but they never seem to give this particular example. It’s always sodium chloride.

Have they been learning about crystal structures? I wonder whether they're meant to draw a little diagram showing the "rock salt" structure, where you have an alternating network of Na and I.

Like, this but replace Cl with I. They're in the same group so will bond in the same way.

Have they been learning about crystal structures? I wonder whether they're meant to draw a little diagram showing the "rock salt" structure, where you have an alternating network of Na and I.

I don't think that's what they'd be looking for in a question about the atoms reacting.
As PP have said, it's analogous to sodium chloride.

I just wondered because it said 'atoms' of each, so it's not just

Na+ + I- --> NaI

I can't remember when they do structures of metals, salts and organic compounds though, so might be barking up completely the wrong tree!

One Sodium atom loses one electron to form an Na+ ion. This electron is transferred to the iodine atom, which gains one electron to form an I- ion. Strong electrostatic force of attraction between the oppositely charged Na+ and I- ion, and since one Na+ ion reacts with one I- ion, this forms a giant ionic lattice of NaI.

Agree with PPs, it’s an ionic bonding question.

This is probably the relevant page from Bitesize

www.bbc.co.uk/bitesize/guides/ztc6w6f/revision/1