Respuesta :
The moles of sodium ions were present in the solution before the reaction proceeded is 0.36moles
Molarity of a solution
The formula for calculating the molarity of a solution is expressed as:
Molarity = moles/volume
Given the following parameters
Molarity = 4.00M
Volume of sodium sulfate = 45mL = 0.045L
Substitute to have;
Molarity = 4 * 0,045
Molarity = 0.18
Since there are 2 atoms of sodium ion in the solution, hence the moles of sodium ions were present in the solution before the reaction proceeded is 0.36moles
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