Highland Science Department

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Highland Science Department Concentration
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Highland Science Department Concentration Concent
ration the amount of solute per quantity of
solvent
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Highland Science Department Concentration Methods
of determining concentration 1. mass/volume
solute mass (g) x 100 solution
volume (mL)
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Highland Science Department Concentration Methods
of determining concentration 1. mass/volume
solute mass (g) x 100 solution
volume (mL) e.g. saline solution that contains
0.9 g of sodium chloride dissolved in 100
mL 0.9 (m/v)
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Highland Science Department Concentration Methods
of determining concentration 2. mass/mass
solute mass (g) x 100 solution
mass (g)
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Highland Science Department Concentration Methods
of determining concentration 2. mass/mass
solute mass (g) x 100 solution
mass (g) e.g. 100 g of toothpaste contains 0.76
g of sodium fluoride 0.76 (w/w)
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Highland Science Department Concentration Methods
of determining concentration 3. volume/volume
solute volume (mL) x 100
solution volume (mL)
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Highland Science Department Concentration Methods
of determining concentration 3. volume/volume
solute volume (mL) x 100
solution volume (mL) e.g. 100 mL of rubbing
alcohol contains 70 mL of isopropyl alcohol in
water. 70 (v/v)
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Highland Science Department Concentration concent
rations of very trace amounts of solute (e.g.
pollutants) can be expressed as parts per
million (ppm) parts per billion (ppb) parts
per trillion (ppt)
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Highland Science Department Concentration parts
per million solute mass x 106
solution mass similar to mg/L
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Highland Science Department Concentration parts
per million solute mass x 106
solution mass similar to mg/L parts per billion
solute mass x 109 solution
mass similar to µg/L
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Highland Science Department Concentration e.g. A
1.6 kg fish was found to contain 0.6 mg of
mercury. If the acceptable level is 0.5 ppm,
would this fish be safe to eat?
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Highland Science Department Concentration e.g. A
1.6 kg fish was found to contain 0.6 mg of
mercury. If the acceptable level is 0.5 ppm,
would this fish be safe to eat? G fish mass
1.6 kg x 1.6 x 103 g mercury mass
0.6 mg x 6 x 10-4 g acceptable level
0.5 ppm
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Highland Science Department Concentration e.g. A
1.6 kg fish was found to contain 0.6 mg of
mercury. If the acceptable level is 0.5 ppm,
would this fish be safe to eat? U safety of the
fish S 1. calculate ppm solute mass x
106 solvent mass 2. compare with
acceptable level
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Highland Science Department Concentration e.g. A
1.6 kg fish was found to contain 0.6 mg of
mercury. If the acceptable level is 0.5 ppm,
would this fish be safe to eat? S 1. ppm 6 x
10-4 g x 106 1.6 x 103 g 0.38 ppm
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Highland Science Department Concentration e.g. A
1.6 kg fish was found to contain 0.6 mg of
mercury. If the acceptable level is 0.5 ppm,
would this fish be safe to eat? S 1. ppm 6 x
10-4 g x 106 1.6 x 103 g 0.38
ppm 2. yes, it's ok to eat the fish because its
concentration is lower than 0.5 ppm
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Highland Science Department Concentration Molar
Concentration the number of moles of solute that
can dissolve in 1 L of solution molar
concentration moles of solute
solution volume (L) C
n V
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Highland Science Department Concentration e.g.
1. A solution contains 5.85 g of sodium chloride
dissolved in 5000 mL of water. What is the
molar concentration of the sodium chloride?
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Highland Science Department Concentration e.g.
1. A solution contains 5.85 g of sodium chloride
dissolved in 5000 mL of water. What is the
molar concentration of the sodium
chloride? G NaCl mass 5.85 g volume 5000
mL x 5.00 L M.M. NaCl 58.5 g/mol
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Highland Science Department Concentration e.g.
1. A solution contains 5.85 g of sodium chloride
dissolved in 5000 mL of water. What is the
molar concentration of the sodium
chloride? G NaCl mass 5.85 g volume 5000
mL x 5.00 L M.M. NaCl 58.5
g/mol U molar concentration
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Highland Science Department Concentration e.g.
1. A solution contains 5.85 g of sodium chloride
dissolved in 5000 mL of water. What is the
molar concentration of the sodium
chloride? n MM V S mass ? mole
s ? concentration
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Highland Science Department Concentration e.g.
1. A solution contains 5.85 g of sodium chloride
dissolved in 5000 mL of water. What is the
molar concentration of the sodium chloride? S
Conc 5.85 g x x 5.85
mol/L 58.5 x 5.00 0.02 mol/L
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Highland Science Department Concentration e.g.
2. What mass of potassium hydroxide is required
to prepare 600 mL of a solution with a
concentration of 0.225 mol/L?
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Highland Science Department Concentration e.g.
2. What mass of potassium hydroxide is required
to prepare 600 mL of a solution with a
concentration of 0.225 mol/L? G conc KOH 0.225
mol/L volume 600 mL x 0.600 L M.M.
KOH 56.1 g/mol
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Highland Science Department Concentration e.g.
2. What mass of potassium hydroxide is required
to prepare 600 mL of a solution with a
concentration of 0.225 mol/L? G conc KOH 0.225
mol/L volume 600 mL x 0.600 L M.M.
KOH 56.1 g/mol U mass of KOH
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Highland Science Department Concentration e.g.
2. What mass of potassium hydroxide is required
to prepare 600 mL of a solution with a
concentration of 0.225 mol/L? n V
MM S concentration ? moles ? mass
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Highland Science Department Concentration e.g.
2. What mass of potassium hydroxide is required
to prepare 600 mL of a solution with a
concentration of 0.225 mol/L? S KOH mass
0.225 mol x x 1 L 0.225 x
0.600 x 56.1 g 7.57 g
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Highland Science Department Concentration e.g.
3. A solution containing 0.125 mol/L of MgCl2 is
required for an experiment. If 87.8 g of solid
MgCl2 is available, what is the maximum volume of
solution that can be prepared?
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Highland Science Department Concentration e.g.
3. A solution containing 0.125 mol/L of MgCl2 is
required for an experiment. If 87.8 g of solid
MgCl2 is available, what is the maximum volume of
solution that can be prepared? G MgCl2 mass
87.8 g concentration 0.125 mol/L M.M. MgCl2
95.3g/mol
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Highland Science Department Concentration e.g.
3. A solution containing 0.125 mol/L of MgCl2 is
required for an experiment. If 87.8 g of solid
MgCl2 is available, what is the maximum volume of
solution that can be prepared? G MgCl2 mass
87.8 g concentration 0.125 mol/L M.M. MgCl2
95.3g/mol U volume
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Highland Science Department Concentration e.g.
3. A solution containing 0.125 mol/L of MgCl2 is
required for an experiment. If 87.8 g of solid
MgCl2 is available, what is the maximum volume of
solution that can be prepared? G MgCl2 mass
87.8 g concentration 0.125 mol/L M.M. MgCl2
95.3g/mol U volume n MM V S mass
? moles ? volume
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Highland Science Department Concentration e.g.
3. A solution containing 0.125 mol/L of MgCl2 is
required for an experiment. If 87.8 g of solid
MgCl2 is available, what is the maximum volume of
solution that can be prepared? S volume 87.8
g x x 87.8 L 95.3 x
0.125 7.37 L