35.53g of Manganese sulphate tetrahydrate were dissolved in 250.0 mL of water. What was the molarity of the solution? If you were to take a 25.00mL sample of the solution, how many manganese ions would be in your sample?
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MnSO4 ∙ 4H2O, molec wt = 223.0582 g/mol
MV = grams / molec wt
(M) (0.2500 L) = 35.53 g / 223.0582 g/mol
M = 0.6637 mol/L
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moles = MV
x = (0.6637 mol/L) (0.02500 L)
x = 0.0165925 mol of Mn^2+ ions (remember that there is a one to one molar ratio between MnSO4 and Mn^2+ ion in solution)
0.0165925 mol times 6.022 x 10^23 ions / mol = the answer you seek
MV = grams / molec wt
(M) (0.2500 L) = 35.53 g / 223.0582 g/mol
M = 0.6637 mol/L
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moles = MV
x = (0.6637 mol/L) (0.02500 L)
x = 0.0165925 mol of Mn^2+ ions (remember that there is a one to one molar ratio between MnSO4 and Mn^2+ ion in solution)
0.0165925 mol times 6.022 x 10^23 ions / mol = the answer you seek