Molarity

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Molarity
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Concentration is defined as the amount of solute
in a given volume of solution Molarity (M)
describes the amount of solute in moles and the
volume of the solution in liters
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Molarity (M) is the number of moles of solute per
volume of solution in liters.
moles of solute liters of solution
mol L

M molarity
A solution that is 1.0 molar (1.0 M) contains 1.0
mol of solute per liter of solution.
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Calculate the molarity of a solution prepared by
dissolving 11.5g of solid NaOH in enough water to
make 1.50L of solution.
Mass of solute 11.5g NaOH Volume of solution
1.50L
moles of solute liters of solution
M
5
Calculate the molarity of a solution prepared by
dissolving 11.5g of solid NaOH in enough water to
make 1.50L of solution.
Mass of Solute
Moles of Solute
Molarity
Use molar mass
Moles / Liters
6
Calculate the molarity of a solution prepared by
dissolving 11.5g of solid NaOH in enough water to
make 1.50L of solution.
Mass of solute 11.5g NaOH Volume of solution
1.50L
1 mole NaOH 40.0g of NaOH
11.5g NaOH x
0.288 mol NaOH
7
Calculate the molarity of a solution prepared by
dissolving 11.5g of solid NaOH in enough water to
make 1.50L of solution.
moles of solute Liters of solution
Molarity
0.288 mol NaOH 1.50L of solution
0.192 M NaOH

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Calculating ion concentration from Molarity

• Give the concentrations of the ions in each of
  the following solutins
• 0.10 M Na2CO3
• 1 M FeCl3

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Calculating ion concentration from Molarity

• 0.10 M Na2CO3

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Calculating ion concentration from Molarity

• 1 M FeCl3

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Acids and Bases
Acids produce hydrogen ions (H) in aqueous
solution Bases produce hydroxide ions (OH)- in
aqueous solution
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Acids and Bases
Acids produce hydrogen ions (H) in aqueous
solution HCl(g) H(aq) Cl-(aq)
H2O
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Acids and Bases
Bases produce hydroxide ions (OH)- in aqueous
solution NaOH(s) Na(aq) OH-(aq)
H2O