i don't know this answer about question?

Question

1) 1.00 mol/L Na3PO4(aq)
2) 2.50 mol/L Na2SO4(aq)
3) 3.00 mol/L CaSO4(aq)
4) 4.00 mol/L NH4NO3(aq)

When the above solutions are arranged in ascending order of the total amount of ions in solution, the four digit number obtained is _ _ _ _

Answer 1

Your question is not very clear, however I am attempting it.
1: 1 mol of Na3PO4 will have 3 mol of Na and 1 mol of PO4 ions.
2: 2.5 mol of Na2SO4 will have 5 mol of Na and 2.5 mol of SO4 ions.
3: 3 mol of CaSO4 will have 3 mol of Ca and 3 mol of SO4 ions.
4: 4 mol of NH4NO3 will have 4 mol of NH4 and 4 mol of NO3 ions.

Answer 2

however not very clear the ascending order can be 1,2,3,4 well how the guy above cleared that or try multiplying no of ions 6.023*10^23 with the no. of moles

Answer 3

The answer is "1-3-2-4".

1.0M sodium phosphate has 3 moles sodium ions, 1 mole phosphate ions. 3 + 1 = 4 moles of ions

2.5 moles of sodium sulfate has 5 moles sodium ions, 2,5 moles sulfate ions. 5 + 2.5 = 7.5 moles of ions

3 moles of calcium sulfate has 3 moles calcium ions, 3 moles sulfate ions. 3+3 = 6

4 moles of ammonium nitrate has 4 moles ammonium ions, 4 moles nitrate ions. 4 + 4 = 8

Arranged in ascending order of the number of moles of ions, you'd have:

1) Sodium phosphate (4 moles total ions)
3) Calcium sulfate (6 moles total ions)
2) Sodium sulfate (7.5 moles total ions)
4) Ammonium nitrate (8 moles total ions)