Write a balanced equation for the dissolution

Question

of sodium carbonate (Na2CO3) in water. Find
the number of moles of Na+ produced when
0.318 mol of sodium carbonate dissolves. Answer in units of mol.

Answer 1

The reaction is
Na2CO3 -> 2 Na+ + CO3(2-)

The balanced reaction equation tells you that each mole of sodium cardonate makes 2 moles of Na+.

So, double the 0.318

Answer 2

0.636