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e. C3000: Sodium Hydroxide – caustic, wear protective gloves and
glasses when handling. You’ll be generating this with your
experiments, so follow all directions carefully.

5. After mixing two chemicals together, you observe your solution
bubbles (generates a gas), gets warm (exothermic) and turns litmus
paper red (acidic).

6. If you cut an apple in half and leave it for ten minutes, it turns brown
because the fruit is basically rusting. An enzyme in the fruit
(polyphenol oxidase) reacts with the oxygen in the air. You can add
lemon juice or other acid to slow this chemical reaction down or by
removing the oxygen (by vacuum sealing the fruit). If you cut the
apple with a rusty knife, the reaction will occur even faster!

7. The balanced equations are below:

a. 3 KOH + H 3PO 4 K 3PO 4 + 3 H 2O

b. 4 NH 3 + 5 O 2 4 NO + 6 H 2O

c. 2 BF 3 + 3 Li 2SO 4 B 2(SO 3) 3 + 6 LiF

8. Let’s figure out how many moles are in 26 grams of CO 2. First, we
peek at the periodic table and find out the atomic mass of carbon is
12, and the atomic mass for oxygen is 16. Here’s how you find the
mass of CO 2:

C + 2 (O) 12 + 2(16) = 44

So one mole of CO 2 weighs 44 grams. This now becomes our
conversion factor of (1 mole)/(44 grams) and we use it like this:

Number of moles of CO 2 = 26g x (1 mole/44grams) = 0.59 moles

So there are 0.59 moles of CO 2 in 26grams.

9. If we have 42 moles of H 2SO 4, how many grams is that?

First, look up H, S, and O in the periodic table to find their atomic
masses: H = 1, S = 32, O = 16. So the atomic mass of H 2SO 4 is:

H 2SO 4 2H + S + 4O 2(1) + 32 + 4(16) = 98

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