formula help please (1 Viewer)

[kr73114]

can someone help me with the formula for the compound formed between (can u please give reason):
1.sulfur and chlorine
2. hydorgen and iodine
3. silcon and hydrogen
4. phosphorous and fluorine

 

[google5678]

Hey,

Im pretty sure that those elements form these compounds-

1. SCl2
2. HI
3. SiH4
4. PF3

As for working it out, i looked at the valencies of the elements and then worked out how many of each would bond to form a valenece shell of 8 (or 2).

eg. H (valence +1) bonds ionically with I (valence -1) to form HI.
and, Sulfur (valence -2) bonds covelently with Chlorine (valence -1) to form SCl2

This isn't a great explanation and i hope someone can explain it better.

 

[x_cp3]

yeah similar to google's explanation, just swap them around so for e.g. Mg has a charge of 2+ and its reacting with Nitrogen which has a charge of 3- it will yield Magnesium Nitride - Mg3N2..