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Concentration Worksheet
1)
How many grams of beryllium chloride are needed to make 125 mL of a
10% solution?
2)
How many grams of beryllium chloride would you find in a 125 mL
aqueous solution if the concentration was 50 ppm? CHANGES MADE TO
QUESTION!!
3)
The density of ethanol is 0.789 g/mL. How many grams of ethanol should
be mixed with 225 mL of water to make a 4.5% (v/v) mixture?
4)
Explain how to make at least one liter of a 5% m/v ammonium hydroxide
solution.
5)
What is the concentration (in g/L, ppm and %) of a solution in which 0.45
grams of sodium nitrate are dissolved in 265 mL of solution.
6)
What is the concentration (in g/L, ppm and %) of sulfuric acid in a solution
made by adding 3.4 grams of sulfuric acid to 3,500 mL of water?
7)
What will the volume of a 0.50 g/L solution be if it contains 25 grams of
calcium hydroxide?
8)
How many grams of ammonia are present in 5.0 L of a 500 ppm solution?
© 2004 Cavalcade Publishing, All Rights Reserved
For chemistry help, visit www.chemfiesta.com
Concentration Worksheet – Answers
1)
How many grams of beryllium chloride are needed to make 125 mL of a
10% solution?
10%m/m = (x/125mL) x 100, x = 12.5g
2)
How many grams of beryllium chloride would you find in a 125 mL
aqueous solution if the concentration was 50 ppm?
50ppm = 50mg/L, 50mg/L = 0.05g/L, 0.05g/L = x/0.125L, x = 0.00625g
3)
The density of ethanol is 0.789 g/mL. How many grams of ethanol should
be mixed with 225 mL of water to make a 4.5% (v/v) mixture?
4.5%v/v = {x mL / (225mL + x mL)} x 100, x = 10.60 mL
10.60 mL X 0.789g/mL = 8.37g
4)
Explain how to make at least one liter of a 5% m/v ammonium hydroxide
solution.
5% m/v = (x g/1000mL) x 100, x = 50g of solute to be added to a
volumetric flask and fill with solvent until a total volume of 1L is achieved.
5)
What is the concentration (in g/L, ppm and %) of a solution in which 0.45
grams of sodium nitrate are dissolved in 265 mL of solution.
g/L = 0.45g/0.265L= 1.70g/L, ppm = 450mg/0.265L = 1698 ppm,
%m/v = (0.45g/265mL)x 100 = 0.17%
6)
What is the concentration (in g/L, ppm and %) of sulfuric acid in a solution
made by adding 3.4 grams of sulfuric acid to 3,500 mL of water?
g/L = 0.97g/L, ppm = 0.00097ppm, %m/v = 0.097%
7)
What will the volume of a 0.50 g/L solution be if it contains 25 grams of
calcium hydroxide?
0.50g/L = 25g/ x L, x = 50L
© 2004 Cavalcade Publishing, All Rights Reserved
For chemistry help, visit www.chemfiesta.com
8)
How many grams of ammonia are present in 5.0 L of a 500 ppm solution?
500 ppm = 500 mg/L = x/5.0 L, x = 2500 mg = 2.5g
© 2004 Cavalcade Publishing, All Rights Reserved
For chemistry help, visit www.chemfiesta.com
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