Molarity Concentration and Parts Per Million 2019.notebook

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April 05, 2019

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Molarity Concentration

Aim: To analyze a solution's concentration using Molarity.

Concentration is based on the amount of solute present in a solution.

Feb 6­1:39 PM

Molarity and MolalityMolarity (M): the concentration of a solution measured in the number of moles of solute per liters of solution.

The larger the number of moles of solute in solution, the higher the molarity concentration.

1.00 L of a 1.0 molar solution     VS.    1.00 L of a 0.10 molar solution    

Molarity Concentration and Parts Per Million 2019.notebook

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April 05, 2019

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Molarity and MolalityMolarity (M): the concentration of a solution measured in the number of moles of solute per liters of solution.

The larger the number of moles of solute in solution, the higher the molarity concentration.

1.00 L of a 1.0 molar solution     VS.    1.00 L of a 0.10 molar solution    moles solute = molarity x liters solutionmoles solute = 1.0 M x 1.00 Lmoles solute = 1 mole

moles solute = molarity x liters solutionmoles solute= 0.10 M x 1.00 Lmoles solute= 0.10 moles

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1. What is the molarity of a 6.00 L solution containing 0.500 moles of glucose?

2. How many moles of sodium chloride must be dissolved to create 2.00 L of a 2.50 M solution?

Molarity Problems

Molarity Concentration and Parts Per Million 2019.notebook

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April 05, 2019

Feb 6­1:39 PM

1. What is the molarity of a 6.00 L solution containing 0.500 moles of glucose?

2. How many moles of sodium chloride must be dissolved to create 2.00 L of a 2.50 M solution?

Molarity Problems

Molarity=     moles solute ;  M = 0.500 moles glucoseliters of solution   6.00 L solution

Molarity=  0.0833 M

Molarity=     moles solute ;  2.50 M = moles NaClliters of solution               2.00 L solution

moles NaCl= 2.50 M x 2.00  Lmoles NaCl = 5.00 moles

Feb 6­1:39 PM

Molarity Problems

3. What is the molarity of a solution containing 196 g of sodium chloride (NaCl) dissolved into 1.85 L of solution?

4. How many liters of a 5.0 molar solution will be produced by dissolving 2.00 moles of sugar in a sufficient amount of water?

Molarity Concentration and Parts Per Million 2019.notebook

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April 05, 2019

Feb 6­1:39 PM

Molarity Problems

3. What is the molarity of a solution containing 196 g of sodium chloride (NaCl) dissolved into 1.85 L of solution?

4. How many liters of a 5.0 molar solution will be produced by dissolving 2.00 moles of sugar in a sufficient amount of water?

Molarity=     moles soluteliters of solution

# moles= given massg.f.m

# moles= 196 g         =3.35 mol58.5 g/mol

convert to moles using gfm

Molarity=  3.35 moles NaCl1.85 L solution

Molarity=  1.81 M

Molarity=     moles solute  ; 5.0 M = 2.00 moles sugarliters of solution  liters of solution

liters of solution= 2.00 moles sugar/ 5.0 Mliters of solution= 0.40 L

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5. How many moles of Ca(NO3)2 are present in 3.8 liters of a 0.45 molar solution?

Molarity Problems

Molarity Concentration and Parts Per Million 2019.notebook

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April 05, 2019

Feb 6­1:39 PM

5. How many moles of Ca(NO3)2 are present in 3.8 liters of a 0.45 molar solution?

Molarity Problems

Molarity=     moles solute; 0.45 M= moles soluteliters of solution 3.8 L solution

moles solute= 0.45 M x 3.8 Lmoles solute= 1.71 mol

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Making a Solution

3. Add enough solvent to the solute to make the TOTAL LITERS of solution. 

1. You always determine the amount of required solute using the appropriate concentration data and formula.

2. Calculate the amount of grams of solute needed from the moles using the GFM. Measure this mass using a balance. 

Make 1.0 L of a 0.10 M C12H22O11 solution.

Molarity Concentration and Parts Per Million 2019.notebook

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Making a Solution

3. Add enough solvent to the solute to make the TOTAL LITERS of solution.  (Solution volume = solute volume + solvent volume)– The solute occupies a small fraction of the volume.

1. You always determine the amount of required solute using the appropriate concentration data and formula.

2. Calculate the amount of grams of solute needed from the moles using the GFM. Measure this mass using a balance. 

Make 1.0 L of a 0.10 M C12H22O11 solution.

Molarity=     moles solute ; 0.10 M = moles soluteliters of solution    1.0 L solutionmoles solute= 0.10 moles

# moles= given mass ; 0.10 moles = given massg.f.m.     342.0 g/mol

given mass= 0.10 moles x 342.0 g= 34.2 grams of C12H22O11 solute

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Molarity Dilution and Parts Per Million

Concentration

Aim: To determine the concentration of diluting a solution and concentration using parts per million.

Molarity Concentration and Parts Per Million 2019.notebook

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April 05, 2019

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Parts per millionParts per million is typically used when working with extremely small quantities of solute in solution.

FORMULA

parts per million = mass of solute x  1000000mass of solution

Ex 3) A solution contains 330 grams of CaCl2 dissolved in 1000 grams of water.What is the concentration of the solution in parts per million?mass solute= 330 g ppm= 330 g x 1,000,000= 248120.3 mass solution= 330 g + 1000 g H2O 1330 g ppm

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Ex 4) A 67.0 g sample of a solution contains 4.7 x 10‐3 grams of lead nitrate. What is the concentration in parts per million of the solution?

Parts per million

mass solute= 4.7 x 10‐3 g ppm= .0047 g x 1,000,000= 70.15 mass solution= 67.0 g 67.0 g   ppm