question about Chemistry?

Question

1.) The total concentration of all the ions in a 1.15 mol/L solution of sodium sulphate is ____________ mol/L

2) Write an equation that describes what happens when the following compounds are put into water:
a)TlCl3
b)C2H5OH
c)Fe2(CO3)3

3) what is the volume of water added to 57.2mL of a 6.50 mol/L HCl(aq) solution in order to prepare a 0.356 mol/L solution

Answer 1

1)
Sodium Sulfate (Na2SO4) will break into ions in solution,
Na2SO4 (s) --H2O--> 2 Na+1 (aq) + SO4-1 (aq)
For every 1 mole of Na2SO4 dissolved, 3 moles of ions are formed. If the concentration of Na2SO4 is 1.15 mol/Liter, then the ion concentration must be 3 times as much, 3.45 mol/Liter.

2)
TlCl3 is an ionic compound which when dissolved in water will break into ions since Chloride compounds are generally soluble,
TlCl3 (s) --H2O--> Tl+3 (aq) + 3Cl- (aq)

C2H5OH, otherwise known as ethanol, will easily dissolve (easily mincible) in water, but will not break into ions (as it is not an ionic compound).

Fe2(CO3)3 (although it is an ionic compound) in considered insoluble in water. Carbonates in generally are considered insoluble unless they are bonded with a group 1 element or the Ammonium ion.

3)
.356 mol/Liter HCl means that for every 1 Liter of solution, there are .356 moles of HCl dissolved in it.
Molarity = moles / Liter --> moles = Molarity * Liters
So if you originally had a 6.5 M solution with a volume of .0572 Liters, you originally had .3718 moles of HCl.

.356 M = .3718 moles HCl / x Liters
x Liters = .3718 moles / .1.044 Liters.

So if then old volume was 57.2 mL and the new volume should be 1044 mL, then 986.8 mL shoudl be added to solution.

Answer 2

1. 1.15 * 3 = plug in your calculator
2. a) it ionizes into Tl3+ and Cl-
b) It disssolves
c) ionzes into Fe3+ and CO3 2-
3. (57.2mL)(6.5 M)/(.356 M) = plug into thy calculating device

Answer 3

Sorry, I only had Chemistry in college and passed with a B, by tutoring. So I am thrilled to not have to do it now. Sorry, um..check out searches on homework help on google or ask.com. I am sure there are people who can help you.

Answer 4

the answer to no.3 should be 0.0031328L