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```Name:______________________________
Concentration and Dilutions
Reminder:
C=m/V
We measure concentration in g/L.
1. What is the sugar concentration of a cup of tea containing 0.25 L of tea and 5 g of sugar?
2. What will be the sugar concentration of the liquid if you pour the cup of tea into a pitcher
containing 2.5 L of unsweetened tea?
3. Read the procedure below and perform the appropriate calculation.
Procedure:
1. Gather materials
2. Place beaker on balance, tare scale.
3. Measure 500mg of solute in the beaker.
4. Dissolve solute in beaker, with a limited amount of solvent.
5. Pour solution from beaker into 100 mL volumetric flask. Fill volumetric flask with solvent.
6. Calculate the concentration of the solution created
Diltution
How would you create a solution with a concentration than one with a concentration of 4g/L?
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How would you decrease the concentration of a solution?
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Dilution is:
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Examples of Dilution in everyday life:
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Calculation of dilution:
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C1 = ______________________ (strong) solution
V1 = ______________________ (strong) solution
C2 = ______________________ (weak) solution
V2 = ______________________ (weak) solution
Reminder:
12 % (m/V) means “ 12 g of solute dissolved in 100 mL of solution”
8 % (m/m) means “ 8 g of solute dissolved in 100g of solution”
10% (V/V) means “10 mL of solute dissolved in 100mL of solution”
Try:
A solution was made using 8g of solute and it has a concentration of 6% (m/m). What is the mass of the
solution?
Vinegar is really just 5% (V/V) acetic acid. What volume of acetic acid is contained in a 600 mL bottle of
vinegar?
Now try this and dilution!
1. How much of a 55 g/L salt solution do you need to prepare 750 mL of a 22g/L salt solution?
2. How much of a 25% (m/V) glucose solution do you need to prepare 50 mL of a 10% (m/V)
solution?
3. How much of a 10g/L acid solution do you need to prepare 500 mL of a 2 g/L acid solution?
4. 2. How much of a 5% (V/V) alcohol solution do you need to prepare 250 mL of a 3% (V/V)
alcohol solution?
5. Your mom asks you to buy and then make orange juice from concentrate for a party at your
house. Here is the information from 3 cans of the juices on the market. Which will you buy?
Your mom wants the lowest sugar content.
A. volume of can = 550ml
Sugar content = 62.15 g
B. volume of can = 330 ml
sugar content = 38.28g
C. volume of can =275ml
sugar content = 30.5g