Initlal mmoles of Cu2+ present in the solution = volume (mL) molarity
= 20.00 2.64 = 52.8
volume of diluted solution = 500.0 mL
then, molarity of Cu2+ in 500.0 mL solution
= (moles / volume)
= (52.8 /500.0 ) = 0.1056 M
again 25.00 mL 0.1056 is taken
so, mmoles in above solution
= 25.00 0.1056
= 2.64
volume of the final solution = 100.0 mL
therefore molar concentration of Cu2+ in 100.0 mL solution
= (moles /volume)
= (2.64/100.0)
= 0.0264 M
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