NATURE OF MATTER-I

 

Period:                                     Duration:             4O MINS each                      Average age of learners: 15

Subject: CHEMISTRY                                                                           Class: SS ONE

Topic:              NATURE OF MATTER - I

Sub topic:  MATTER

Reference materials:

(1) ESSENTIAL CHEMISTRY, TONALD PUBLISHERS, I. O ODESINA

(2) NEW SCHOOL CHEMISTRY, AFRICAN FIRST PUBLISHERS, OSEI YAW ABABIO

(3) INTERNET

Instructional materials:

Entry behavior: The students have been familiar with state of matter

Behavioural objective: At the end of the lesson the students should be able to:

1^st PERIOD

i.                     define matter

ii.                    state some of example of matter

iii.                  state the properties of matter

2^nd  PERIOD

i.                     state the types of changes

ii.                    explain the types of changes

3^rd  PERIOD

i.                     differentiate between physical and chemical changes

4^TH PERIOD

REVISION

                                                                                                  NATURE OF MATTER

1^st PERIOD

STEP I: The teacher defines matter.

Everything in this universe is made up of material which scientists have named “matter”. Matter is anything that has mass and occupies volume. All the things we come across in our daily life are matter. Matter is made up of particles, like sand, sugar, salt. The particles of matter are very small, smaller beyond our imagination.

A definition of "matter" that is based upon its physical and chemical structure is: matter is made up of atoms and molecules. Atom is the smallest unit which cannot be divided further into smaller particles.

STEP II: The students chorus the definition.

STEP III: The teacher states the properties of matter 

PROPERTIES OF MATTER

Matter has properties like density, colour, physical state, hardness, electrical conductivity.

EVALUATION:  The teacher evaluates the lesson by asking the following questions:

I.                     Define matter

II.                    Give 3 example of matter

III.                  State the properties of matter

   2^nd  PERIOD

STEP I: The teacher explains Physical changes with relevant example

There are two type of change. These are physical and chemical change

 Physical changes

A physical change is any change in matter that involves the substance going from one physical state to another. The reference to a physical state involves solids, liquids, and gases. When a substance undergoes a physical change it does not lose its original properties when changing from one phase to another. The types of physical changes can vary. A substance can go from a solid to a liquid, a liquid to a gas, a gas to a liquid, a liquid to a solid, a solid to a gas, or a gas to a solid.

Examples of Physical changes:

1. Ice melting involves a change from a solid to a liquid and the substances maintain the properties of water because the molecules never change.

 2. Water boiling is a physical change as water molecules vibrate faster, they enter the gas phase and become water vapor.

3. Rubbing alcohol left uncovered will evaporate quickly into the air. It turns to a gas but maintains the properties of alcohol.

4. Hot molten iron is a liquid and when left to cool will from solid steel and can take many forms.

 5. Dissolving sugar in water is a physical change. The solid sugar never loses its properties, the molecules become separated by water and the sugar can easily be recovered by evaporating the water.

STEP II: The students are to give examples of physical change apart from the ones mentioned above.

STEPIII: The teacher explains chemical changes with relevant example

Chemical change

A  chemical change is one that affects the internal structure of the substance, so as to form a new substance.

 Observations that suggest a chemical change has occurred include:

o    Production of heat or light

o    Formation of a gas or precipitate

o    Color change.

·         When chemical reactions occur, there is almost always a change in energy, which can be observed as a change in temperature of the reaction mixture.

EVALUATION: The teacher evaluates the lesson by asking the following question:

i.                     state the types of changes

ii.                    explain the types of changes

ASSIGNMENT

Exam Mirror chemistry workbook for ss1, pg 26, Qn 4b

3^rd  PERIOD

STEP I: The teacher revises the previous lesson

STEP II: The teacher states the differences between physical state and chemical changes

Comparison Chart

BASIC FOR COMPARISON	PHYSICAL CHANGE	CHEMICAL CHANGE
Definition	Change in which the molecules are rearranged but their internal composition remains same	A process in which the substance transforms into a new substance, having different chemical composition
Example	Tearing of paper, melting/ freezing of water,	Burning of wood/paper, rusting of iron
Nature	Reversible	Irreversible
Original matter	Can be recovered	Cannot be recover
Involves	Changes in the physical properties of the substance i.e shape, size ,colour.	Changes in the chemical properties and composition of the substance
Product formation	No new product is formed	New product is formed
Energy	Absorption and evolution of energy do not take place	Absorption and evolution of energy  take place during reaction

 

Evaluation: The teacher evaluates these lessons by asking the following questions:-

i.                     differentiate between physical and chemical changes

 Assignment

Exam Mirror chemistry workbook for ss1, pg 26, Qn 4a