LESSON TRANSCRIPT

INDUCTIVE THINKING MODEL(Arun)

Name of school        : Model Boys H.S.S                                                              Standard        : VIII Name of teacher       : Arunbose. A                                                                       Strength         : Subject                       : Chemistry                                                                           Date                : Unit                            : Molecule, Atom                                                                 Duration        : Topic                          :  Homogeneous and heterogeneous mixtures

                                                                               

Name of the concept: Homogeneous and heterogeneous mixtures

OBJECTIVES:

Ø  Pupils develop observation skill.

Ø  Identification of different types of homogeneous and heterogeneous mixtures.

Ø  Generalization about the properties of homogeneous and heterogeneous mixtures.

Ø  Pupils develop hypothesing predicts results.

PHASE 1: DATA CATEGORISATION

T: What is the common property of salt solution, sugar solution, muddy water, lemon            juice etc.? 

S: They all are solutions.      

T: Ok. If I add soil and air to the above list, then can you find any other common property?   

S: They all are mixtures.

T: Can you name some more mixtures?

S: Starch, gold, steel etc.

T: Can you group them on the basis of their similarities?

A	B
Salt solution	Starch
Sugar solution	Rock
Milk	Muddy water
Air	Soil
Steel	Sand

PHASE 2: INTERPRETATION OF DATA

T: Now let us analyze the above mentioned examples. How did you classified them/

S: Items in group A are mainly liquid solution.

T: Then what about air and steel?

S: The components of group A mixtures are not visible.

T: What about group B mixtures?

S: The different components of group B mixtures are not easily visible.

T: Right. Anything more?

S: The components in group A mixtures are uniformly distributed whereas the components in group B mixtures are localized.

T: Absolutely right. Can you name them?

T: They are homogeneous and heterogeneous mixtures.

Homogeneous mixtures are mixtures where the components that make up the mixture are uniformly distributed. Heterogeneous mixtures are the mixtures in which components can be seen as if there were three or more phases are present.

PHASE 3: APPLICATION OF GENERALISATION

T: Now I will give you some examples. Identify them?

    Dust

S: Heterogeneous mixture.

T: Right. Why it is heterogeneous?

S: Because dust particles are easily visible.

T: Yes, then clay.

S: Heterogeneous.

T: Milk.

S: Homogeneous.

T: Gravel.

S: heterogeneous.

T: All right. So heterogeneous mixtures are mixtures where the properties are not uniform        throughout, whereas in homogeneous mixtures the properties are uniform throughout.