The moles of sodium chloride we need to make 500mL solution is 0.125 mole.
Molarity of any solution tells about the concentration and it is define as the no. of moles of solute present in per liter of solution, and it is represented as:
M = n/V, where
M = molarity of given NaCl solution = 0.250M
V = volume of NaCl solution = 500mL = 0.5L
No we put these values on the above equation and calculate for n, we get:
n = (0.250M)(0.5L) = 0.125 mole
Hence, required moles of NaCl is 0.125 mole.
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