HEAT CHANGE OF MATTER

HEAT

CHANGE OF MATTER

Activity 6.1

I.       Purpose                                 :

Determining the melting point and boiling point of water,

II.       Basic Theory                         :

     A substance can change from one form to another (change form) whether changes in physical (physical properties) and chemical changes (chemical properties). Examples of changes in the form of a substance that is as follows:

1. Changes in physics

     Changes in physics is the change of a substance without producing a new substance. Changes in physics is divided among several other categories:
Evaporation

Condensation

Freezing

Defrost

Sublimations

Crystallization

2. Chemical changes

     Chemical changes are changes of a substance that produces new substances that are different from the nature of the substance of origin. Chemical changes also called shape changes that occur due to chemical reactions. Examples of chemical changes in everyday life are:

Paper being burned to ashes

Cooking oil Yeng has oxidized and become rancid

Iron is placed in the soil become rusty

Wood is burned for cooking

Items that have expired, and others.

III.       Materials and Equipments      :

·           Lap 100 mL beaker or paper towels

·           Test tube big

·           Stative and brace

·           Thermometer -10 ° C - 150 ° C

·           Aquades

·           Wire gauze

·           Salt kitchen

·           Leg three

·           Ice

·           Burner methylated spirit

·           Tap water

·           Matches

IV.       Step Work                           :

1.      Arrange the equipment.

2.     Enter the ice granules are made of pure water into a beaker of clean and dry.  Then, pour a little pure water into the beaker so that no empty space between the grains of ice .Immerse tip of the thermometer into the beaker. Eforts for the end of the thermometer is located in between the grains of ice. Observe the temperature changes that occur after submerged in between grains of ice. Record the temperature when the thermometer indicated no change again. Turn on the burner methylated spirit and strive for the flame that comes out relatively remained the same throughout the experiment. Record the temperature every interval of 2 minutes after the fire ignited. Heating continued until the temperature of boiling water does not change anymore.

V.       Task                                     :

1.     What is the melting point and boiling point?

2.    Why when there are changes form, not substance temperature change?

Activity 6.2

 MATTER CHANGES AND CHEMICAL REACTIONS

I.       Purpose                                 :

To learn about chemical changes

II.       Basic Theory                         :        

     During the occurrence of chemical changes, the chemical reaction is also taking place. Chemical reaction is the phenomenon of chemical change from reactant into product. Chemical reaction always produces new substances with new composition and characteristic that are different from the original characters. An example, sugar that react with sulphuric acid are called reactant, the chemical substance which is already existed before the chemical reaction happens, whereas carbon and water are products of the new chemical substances produced by the chemical reaction.

III.       Materials and Equipments      :

§              Oranges

§              White paper

§              A small bottle

§              A pipette

§              A brush

§              A small bowl

IV.       Step Work                           :

1.                                                                                                      Squeeze the oranges into a reaction tube by using a funnel.

2.     Put some water into another reaction tube then add a few drops of iodine into that tube

3.     Use a brush to write down your message with the oranges distillation on the white paper

4.                                                                                                     Dry up the paper until the writing is parched

5.     After the writing is parched, brush it with the mixture of iodinr and water

6.                                                                                                     Observe the changes that happen to the paper.

V.       Task                                     :

1.     Why should we read the writing in the experiment using iodine solution?

2.    Guess the kinds of materials that can be used to write secret messages other than oranges extract!