Question

If the formula for a compound is represented by XY2 and the charge on the Y ion is -2, what is the charge in the X ion? (2 points)

+3
+1
+4
+2

Answer 1

assuming an ionic compound and that the total charge of XY2 is zero

Answer 2

just looking at XY2, we know that the compound consists of 1 X and 2 Y

its given that Y has a charge of -2
so the total sum of charges from the Y must be -4

Answer 3

so what would the resulting charge of the X ion be in order to cancel out a charge of -4 in order to result in a net charge of zero?

Answer 4

+2?

Answer 5

well

+2 -4 results in a net charge of -2

we need a net charge of 0 so an ion with a charge of +2 is incorrect

Answer 6

4

Answer 7

@sooobored

Answer 8

+ 4 -4 will produce a net charge of 0

so i would agree with that answer

anything to add? @agent0smith

Answer 9

thanks

Answer 10

I think your way is easier @sooobored

Since you know the charge on Y is -2, it would look like this, before bringing down the charges

\(\Large X^{?} Y^{-2}\)
then after bringing down the charges, it looks like this:
\(\Large X_2 Y_?\)
and you know it looks like
\(\large XY_2\)

Which means it must have been \(\Large X_2 Y_4\) before simplifying.

Answer 11

oh that makes sense. thanks :)