This document describes an experimentation in chemistry lesson. Students will perform various experiments involving physical and chemical changes. They will observe the burning of candles, the mixing of substances like vinegar and baking soda, and the dissolving of solids like salt and sugar. The goal is for students to understand the differences between physical and chemical changes and be able to classify changes as one or the other. They will also discuss the requirements for burning and the products of combustion.

1. .
EXPERIMENTATION IN
CHEMISTRY I

2. .
Experiment No. 1
Experimentation in Chemistry
Theory:
Chemist (scientists) make a great deal of
experimentation as they apply scientific
methods of study. The greatest part in a
chemist’s activities is spent in experimentation.

3. .
You too, as beginning chemists, will have
to perform experiments that will enable to
solve problems you will encounter in the
study of chemistry.

4. .
When gold and silver alloys are molded or
shaped into fine jewelries, no new substances is
formed. Only a change in physical form (shape)
occurs. Hence, this is called a physical change.
For example, when solid water (ice) is heated, it
first changes to liquid water and finally to steam.

5. .
There is no change in the composition of the
substance, only in the form in which it exists.
Consider the change that takes place when
salt dissolves in water. Even though the form
of salt changes, the composition does not. It
is still sodium chloride (NaCl), but now it is
dissolved in water.

6. .
. A chemical change occurs when new
substances is formed. The new substance have
properties entirely different from those of the
original substances. The original substances are
called reactants; the new substances formed are
called products.

7. .Burning candle is an example of chemical
change. When a candle burns it produces heat,
flame, and soot. Soon the candle disappears,
actually two new substances are formed-
carbon dioxide and water vapor. You do not see
these products because they are lost to the
atmosphere.

8. In this activity, you will perform some
common laboratory techniques in order to
identify the characteristics of physical and
chemical changes.

9. .
.OBJECTIVES:
a) To know what are needed for burning to take
place.
b) To know the products of burning.
c) To know the gases and the particles that makes
up the air.

10. .
d) To differentiate physical changes from
chemical changes
e) To classify some changes as physical and
chemical

11. .MM
APPARATUS/ MATERIALS

12. UNLIGHTED CANDLE
.

13. MATCHSTICKS
.

14. CARDBOARD
.

15. .
.

16. MOTHBALLS

17. VINEGAR
.

18. .
BAKING SODA

19. BEAKER
.

20. DRINKING GLASS
.

21. CRUMPLED PIECE OF PAPER

22. ERLENMEYER FLASK
.

23. EGG
.

24. SUGAR
.

25. EVAPORATING DISH
.

26. IRON FILINGS
.

27. MAGNET
.

28. .
.

29. TEST TUBES & TEST TUBE RACK
.

30. .MAGNESIUM RIBBON
.

31. .
.PROCEDURES

32. .
.1. Quickly blow out the candle flame and
quickly relighted the candle at the column of
smoke ½ cm from the wick. Record your
observation. See Figure 1

33. FIGURE 1
.

34. .
2. Move a horizontally held piece of cardboard
quickly down over the flame of a burning
candle. Take note, do not burn the cardboard.
Record your observation.

35. ‘.
3) a) Invert a beaker over a lighted candle.
Take note the time the flask completely
covered the candle and the time the candle
flame is put off. See Figure 2.
Record your observation.

36. FIGURE 2
.

37. .
.b) Relight the candle, invert a smaller beaker
over the lighted candle. Take note again the
candle flame is extinguished.

38. .
.4) Fill a beaker with cold water. Add one (1)
teaspoon of vinegar, then add one teaspoonful of
baking soda. Stir well. Quickly drop the mothballs.
See Figure 3.
Record your observation after a few minutes.

39. FIGURE 3
.

40. .
.5) Place a sheet of crumpled paper inside an
empty glass. Let it rest at the bottom. Put the
glass mouth down into the beaker full of water.

41. .
Push the glass slowly into the water until it
reaches the bottom of the beaker. Get the paper
from the glass. Is the paper wet or dry?

42. .
6) Use a hard-boiled egg with its shell removed.
Light a piece of paper and drop it into an
Erlenmeyer flask or a wide-necked bottle. Place
the egg (sharp end down) on the flask and observe
what happened. See Figure 4.

43. FIGURE 4
.

44. .
.
7) Ignite 2 ml of alcohol in an evaporating dish
Record your observations:
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__________________________________

45. .
.8) Allow 2 ml of alcohol to stand in a watch glass
for five minutes. See Figure 5.
Observations:
_____________________________________
_____________________________________
_____________________________________

46. FIGURE 5
.

47. .
9) Place 5 grams of iron fillings in a watch glass
and magnetize.
Record your observations:
______________________________________
______________________________________
______________________________________

48. .
10) Place a small pieces of ice cubes in a beaker
for a few minutes. See Figure 6.
Record your observations:
___________________________________
___________________________________
___________________________________
Record

49. FIGURE 6
.

50. .
’11) Burn a small piece of magnesium ribbon.
See Figure 7.
Record your observations:
____________________________________
____________________________________
____________________________________

51. FIGURE 7
.

52. .
12) Dissolve a pinch of sodium chloride
crystals in 10 ml of water.
See Figure 8.
Record your observations:
___________________________________
___________________________________
___________________________________

53. FIGURE 8
.

54. .
13) Dissolve one spoonful of sugar in 4 spoonful
of vinegar.
Record your observations:
___________________________________
___________________________________
___________________________________

55. .
14) Dissolve one spoonful of baking soda in 4
spoonful of vinegar.
Record your observations:
_________________________________
_________________________________
_________________________________

56. .
For Discussion: Answers to be submitted next
meeting:
1. What are the requirements for burning to take
place?
2. What are the product of burning?
3. What are the gases and particles that makes
up the air?

57. .
4) In procedure 5, is the paper wet or dry? What
is the reason behind?
5) Which of the substances have undergone
chemical changes?
6) Which of the substances have undergone
physical change?
7) Differentiate chemical change from a physical
change.

58. .
CONCLUSION

59. .
Conclusion:
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