GAMSP INTRODUCTION TO SOLUTIONS CHEMISTRY WORKSHEET
1. What is 3% of 100? Show your calculations.
2. What is 6% of 300?
3. Are all molecules the same size? Think about the size of sodium chloride (aka table salt) in
which each molecule is composed of one sodium molecule atom and one chlorine atom (NaCl).
Compare this to sucrose (aka sugar), in which each molecule is composed of 12 carbon atoms,
22 hydrogen atoms, and 11 oxygen atoms (C12H22O11).
4. Suppose there are three different types of LEGO bricks available, single LEGO bricks (1g), double
LEGO bricks (2g), and DUPLO LEGO bricks (8g). Sally weighs out 24g of the single LEGO bricks,
while John weighs out 24g of the double LEGO bricks and Joan weighs out 24g of DUPLO LEGO
bricks. Who is going to have more fun building castles with their LEGO bricks? Why?
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5. How could you use a scale to distribute LEGO bricks fairly, such that each person gets the same
number of LEGO bricks regardless of the type of brick (e.g. Sally gets 80 single LEGO bricks, John
gets 80 double LEGO bricks, and Joan gets 80 DUPLO LEGO bricks).
6. Think of some situations in which you might want to distribute different items based on weight,
even though some individuals might get more of their given item.
7. Think of some situations in which you might want to distribute different items based on item
number, even though some individuals might get a larger amount due to some items having a
greater mass.
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Solution Dilution
8. Dave wants to make orange juice using a frozen concentrate. The concentrated juice contains
four times more orange syrup than is typically consumed. How should he go about making
orange juice for his breakfast? What would happen if he added too much water? What would
happen if he added too little water?
9. What other household items can you think of that come as a concentrated liquid, but are used
in a diluted form? Why do companies sell items in a concentrate that has to be diluted?
Wouldn’t it be easier if they were sold at the concentration that the consumer needed for use?
10. Define these two phrases: concentrated stock solution and diluted working solution.
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Calculations
Percent Solution: X % * Y ml = Z g
Molar Solution: W fw * X M * Y L = Z g
Dilutions: c1v1 = c2v2
11. How many grams of NaCl (fw = 58.44 g/mole) do you need to make 250ml of a 5% NaCl
solution?
12. How many grams of sucrose (fw = 342.30 g/mole) do you need to make 250ml of a 5% sucrose
solution?
13. How many grams of NaCl (fw = 58.44 g/mole) do you need to make 250ml of a 0.75M NaCl
solution?
14. How many grams of sucrose (fw = 342.30 g/mole) do you need to make 250ml of a 0.75M
sucrose solution?
15. How could you make 100ml of a 2.5% diluted working solution of NaCl from your 5%
concentrated stock solution?
16. How could you make 250ml of a 0.25M diluted working solution of sucrose from your 0.75M
concentrated stock solution?
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