[jango62301]

I am hoping that someone can help me out.  I feel a little foolish having to ask for help on this.  I am an 11th grade AP Chemistry student and am getting ready for my first AP Exam.  Our teacher gave us a bunch of old exams.  I have been able to answer almost all of the questions except for this one.  Can someone help me out?

An 88.5 mL sample of a certain solution of K2SO4 contains 4.69X10^21 SO4- ions.  Determine the number of K+ ions in 13.6 mL of the same solution.  K2SO4 is a strong electrolyte.

I have tried for hours to find an a way that I could solve this with no luck.  The answer choices are:

a.)  3.45 X 10^18 K+ ions
b.)  6.82 X 10^19 K+ ions
c.)  10 K+ ions
d.)  3.60 X 10^20 K+ ions
e.)  2.11 X 10^21 K+ ions
f.)  1.44 X 10^21 K+ ions
g.)  6.32 X 10^22 K+ ions
h.)  9.38 X 10^21 K+ ions

If anyone can give me some guidance I would be extremely appreciative!  Thank you in advance for any assistance!

[Ben Bob2]

Hey, Jango, and welcome to the forum.
Note two very important things about this problem:
1) The ratio of SO₄^2- to mL of solution will remain constant. 
2) The concentration of K⁺ will be twice as much as the concentration of SO₄^2-

Because of #1, you can set the amount of SO₄^2- equal to x, and solve it algebraically.

With these points in mind, give it another shot. Also, show your work so that we can see exactly where things go wrong if you get stuck again.

[jango62301]

Thank you for your *delete me*  Sorry I didn't get a chance to reply until now!  If I did things correctly I came up with F (1.44X10^21) K+ ions.  Did I get the correct answer?

[jango62301]

Why does it not like when I type in h e l p.  It keeps saying *delete me**, kind of funny

[Ben Bob2]

That's the answer I got too, so I think you're right.
People generally overuse the H word on forums like this, so the creators censor it to avoid redundancy (or something like that)
Best of luck with the exam.