Science

Form-4 1st Term

Name: .

Work Sheet (3)

New Manor House School-Dokki 1

A- Complete:

1- The types of change that occur to matter are . types.

2- Fermentation of fruit produces a new ...... with new ..

3- Iron rusts when it is exposed to . and ..

4- Charring of bread is a .. change.

5-The change in the structure of matter is called change.

6-Melting of wax is a . Change, while burning of wax is a

change.

7-The chemical change produces . Substance with a new

..

8-Dissolving sugar in water is a .. change, while iron rusting

a change.

9-Adding yeast in baking is considered a .a change.

10-Production of yoghurt from milk is a ....change, and the digestion

of food is a .change.

11-Granding a quantity of sugar is a .change, while burning

an amount of sugar is a .change.

12-Charring of bread is a change.

13-Ductility of copper into wire is a ..change.

14- Dissolving of table salt in water is considered as a .. change.

15- The chemical change is a change in the

16- Grinding a quantity of sugar is a change, while burning, of

sugar is a . change.

17- The physical change is a change in the ..of the substance

without any change in its ..

Science

Form-4 1st Term

New Manor House School-Dokki 2

B- What happens when?:

1- We put water bottle in the freezer for a day.

Answer: Physical change and water changes to ice.

2-We burn a piece of paper.

Answer: Chemical change and black ash is formed.

3- We heat a piece of sugar strongly.

Answer: chemical change and sugar will burn (brown) substance is

formed.

4- We expose a cold glass sheet to water vapour.

Answer: Drops of water are formed due to the condensation of water

vapour.

5- You put a piece of wax at one end of a sulphur bar and expose the

other end to a candle flame.

Answer: The wax does not melt (sulphur is a bad conductor of heat).

6- You heat a piece of copper and some crystals of sulphur to a high

temperature.

Answer: The sulphur crystals melt before the piece of copper.

C- Give reason:

1- Copper is used in the manufacture of electric wires.

Answer: Because it is a good conductor of electricity.

2- Cooking pans are made of aluminum.

Answer: Because aluminum is a good conductor of heat.

3- Air is a gas.

Answer: Because it does not have a definite shape or volume.

4- Milk is a liquid

Science

Form-4 1st Term

New Manor House School-Dokki 3

Answer: Because it has a definite volume and it does not have a

definite shape.

5- Formation of water drops on the outer surface of a bottle filled with

ice.

Answer: Water vapour in air will condense on the bottle.

6- Ice changes into water if a beaker of ice exposed to air.

Answer: Because ice takes heat from the air, so it melts.

7- Sulphur is an element.

Answer: Because it is on the simplest form of matter that can not be

analyzed into two substances or more.

8- Although carbon is a non-metal, it is used in making the electrode of

dry cells.

Answer: Because it is a good conductor of electricity.

9- Wood burning is a chemical change.

Answer: Because burning of wood causes a change in its shape and

structure producing a new substance with new properties.

10- Metting of wax is a physical change.

Answer: Because melting of wax causes a change in the shape of wax,

but not in its structure.

11- Rusting of iron is considered a chemical change.

Answer: Because it is a change in shape and structure producing a

new substance.