identify the following as either ionic or covalent compounds.. ?

Question

1) sulfur trioxide -
2) phosphorus pentachloride
3) calcium flouride
4) lithium oxide

(: thanx.
and also. wats ionic and covalent ? what's the difference?

Answer 1

an ionic compound is between a metal (on the left of the periodic table) and a non-metal (on the right of the periodic table) Remember that zig zag line of semi-metals (metalloids)? That divides the metals and non-metals.
So- 3 and 4 are ionic. In ionic compounds an electrons is transferred from metal to non metal making a + ion and a - ion.
1 and 2 have two non-metals and are covalent. neither element whats to give up electrons so they share electrons. There is not a strong + or - charge.

Answer 2

1) covalent
2) covalent
3) ionic
4) ionic

ionic bonds are between a metal and a nonmetal, and covalent is between two non metals