Step 1
Data provided:
Concentration of the solution = 4 M (or 4 mol/L)
Volume of the solution = 4 L
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Step 2
Molarity = moles of solute/volume of the solution (L) (1)
Molarity = mol/L or M
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Step 3
The moles of solute must be cleared from (1):
Moles of solute = molarity x volume of the solution
Moles = 4 mol/L x 4 L = 16 moles
Answer: moles of solute = 16 moles