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Unit 1 Chemical reactions Lesson 1

Chemical combination Lesson 2

Chemical compounds Lesson 3

Chemical reactions

Unit 2 Force and Motion Lesson 1

Universal forces in nature Lesson 2

Accompanied forces with motion Lesson (3)

Wave motion

Unit 3 Earth and universe Lesson 1

Celestial bodies Lesson 2 The earth Lesson 3 Rocks and minerals Lesson 4

Earthquakes and volcanoes

1


Unit 1 Chemical reactions Lesson 1

The atom and the ion

Chemical combination

Number of well known elements till now is 112. Elements can be divided into 3 types: Metals 

Solids having luster (except mercury which is liquid).  Good conductor of heat and electricity.  Malleable and ductile.  They contain from 1 3 electrons in their last energy level  They tend to lose electrons.  They change into positive ions. Na ) ) ) Na ) )+ 2 8 1 2 8 p= 11 p=11 e=11 e= 10 +ve ion Mg ) ) ) 2 8 2 p= 12 e= 12

Mg ) )++ 2 8 p= 12 e= 10

Non-metals 

     

Solids or liquids with no luster (except bromine which is a liquid) Bad conductor of heat and electricity (except graphite). Not malleable or ductile. They contain from 5 7 electrons in their last energy level. They tend to gain electrons. They change into negative ions.

Cl ) ) ) 287 p= 17 e= 17

Cl ) ) )2 8 8 p= 17 e= 18 -ve ion O)) O ) )- 2 6 2 8 P=8 p=8 e=8 e = 10

Positive ion It is an atom after losing one or more electrons during a chemical reaction.

Negative ion It is an atom after gaining one or more electron during a chemical reaction. 2

Inert gases  

    

Inactive gases They have 8 electrons in their last energy level, (completely filled) except Helium 2 electrons. They don’t need chemical combination with another atom Their molecules consist of one single atom. They are not expected to form positive or negative ions.


N.B.: Atoms of elements react together to reach the stability of the nearest inert gas.

Chemical bonds Ionic bond It is a bond resulting from the electric attraction between positive ion and negative ion. In ionic bonding, electrons are completely transferred from the atom of a metal to the atom of a non-metal.

Examples

Covalent bond It is a bond resulting from the combination of non-metallic elements by sharing electrons.

Types of covalent bonds Single: a pair of electrons between 2 atoms (one electron from each atom).

Examples

3


Double: 2 pairs of electrons between 2 atoms (2 electrons from each atom).

Examples

Triple: 3 pairs of electrons between 2 atoms ( 3 electrons from each atom).

Examples

4


Lesson (1)

I. Give reason for: a) When an atom loses an electron or more it became a positive ion. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b) The bond in an oxygen molecule is double covalent. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c) The bond in the molecule of magnesium oxide (MgO) is an ionic bond. (Mg=12, O=8) …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

II. Compare between: Metals and non-metals Metals

Non-metals

Positive ion and negative ion Positive ion

Negative ion

Ionic bond and covalent bond Ionic

Covalent

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III. Draw an illustrated diagram for: a) The bond in N2 molecule. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b) The bond in H2O molecule. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c) The bond in CO2 molecule. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

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Lesson 2

Chemical compounds

Valency It is the number of electrons lost , gained or shared by an atom during a chemical reaction.

Examples

Valency = 1

The element

Symbol

Valency

The element

Symbol

Valency

Lithium Potassium Sodium Calcium Magnesium Aluminum Zinc Iron Lead Copper Mercury Silver Gold

Li K Na Ca Mg Al Zn Fe Pb Cu Hg Ag Au

1 1 1 2 2 3 2 2 or 3 2 1 or 3 2 1 3

Hydrogen Oxygen Nitrogen Chlorine Fluorine Bromine Iodine Sulfur Phosphor Carbon

H O N Cl F Br I S P C

1 2 3 or 5 1 1 1 1 2, 4 or6 3 or 5 4

The atomic group (radical) It is a set of atoms joined together and act as one atom during a chemical reaction, having its own valency. Atomic group

Symbol

Valency

Atomic group

Symbol

Valency

Hydroxide Nitrate Bicarbonate Ammonium Nitrite

OHNO3HCO3NH4+ NO2-

1 1 1 1 1

Sulphate Carbonate Phosphate

SO4- CO3- PO4- - -

2 2 3

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Chemical Formula It is a formula that represents the number and type of atoms in a molecule.

How to write the chemical formula of a compound?  Write the symbol of element or atomic group forming the compound.  Write the valency of each element or atomic group.  Cross-multiplication for numbers written. Complete the following table: Compound

chemical formula

Sodium carbonate

Na2CO3

Copper carbonate

CuCO3

Sodium hydroxide

NaOH

Magnesium hydroxide

Mg(OH)2

Aluminium sulphate

Al2(SO4)3

Calcium carbonate

CaSO4

Sodium oxide

Na2O

No. of atoms

No. of elements

Types of compounds In nature there is a countless number of existing compounds. There are acids, bases, salts and oxides. Type of compounds Acids

Bases

Name

Chemical formula

Hydrochloric Acid

HCl

Sulphuric Acid

H2S04

Nitric Acid

HNO3

Sodium Hydroxide

NaOH

Potassium Hydroxide

KOH

Calcium Hydroxide

Ca(OH)2

8


Acids They are materials that dissolve in water producing positive ions of hydrogen (H+). Properties of acids 1. Sour taste 2. Changing the colour of litmus into red due to the presence of the hydrogen ion (H+). Acids can be either : a. Mineral acids called oxygenated acids such as H2SO4 (sulphuric acid) or HNO3 (nitric acid). b. Non-oxygenated acid like HCl ( hydrochloric acid).

Bases They are compounds that dissolve in water producing negative hydroxide ion ( OH )Properties of bases a. Aqueous solutions of bases taste bitter and feel slipper. b. Changing the color of litmus paper to blue due to the presence of OH-

Oxides a. An element combined with oxygen. b. Metal oxide such as sodium oxide Na2O or aluminum oxide Al2O3. c. Non-metal oxide such as carbon dioxide CO2 or sulfur dioxide SO2.

Salts They are produced as a result of the combination of a positive metal ion (or positive atomic group) with a negative ion or a negative atomic group (except oxygen). Properties of salts a. They exist in earth’s crust or dissolved in water. b. They are different in some of their properties such as taste, color, smell, solubility in water and others. Salts that dissolve in water

Salts that don’t dissolve in water

Sodium chloride NaCl Potassium sulphate K2SO4 Calcium nitrate Ca(NO3)2 Magnesium carbonate MgCO3 Sodium sulphide Na2S

Silver chloride AgCl Lead bromide PbBr2 Lead sulphate PbSO4

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Lesson (2)

I.

Write the chemical formula for each of the following:

a. Sodium nitrate …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b. Calcium carbonate …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c. Nitric acid …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… d. Aluminum hydroxide …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… e. Ferric chloride …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

II.

Define each of the following:

a. Valency …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b. The atomic group …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c. The acid …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… d. The base …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

III.

Compare between Acids and Alkalis : Acids

Alkalis

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Lesson 3

Chemical reactions Chemical reaction It is breaking of bonds in reactants molecules and formation new bonds in the products.

Chemical equation It is a set of symbols and chemical formulae representing the reactants, the products and the condition if existed. A chemical equation should be balanced : Number of reactant atoms of an element = number of its atoms produced. The total amount of reactants masses = the total amount of products masses.

N.B. : A chemical reaction is always accompanied with a thermal change. Exothermic reactions They are reactions accompanied by evolution (releasing) of heat.

+ heat Endothermic reactions They are reactions that need heat energy absorption to be occurred.

+ heat

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Types of chemical reactions Direct combination reactions a. An element combines with another element : Carbon + oxygen C

carbon dioxide.

+ O2

CO2

Magnesium + oxygen

+

heat

magnesium oxide . heat

2Mg +

O2

2MgO

b. A compound combines with another compound : Reaction of ammonia with hydrochloric acid forming a white cloud of ammonium chloride. NH3

+

HCl

NH4Cl

Thermal decomposition reactions Copper carbonate CuCO3 (green)

copper oxide + carbon dioxide. heat

CuO (black)

+

CO2

Sodium nitrate decomposes partially producing sodium nitrite and oxygen. heat NaNO3 NaNO2 + O2 (white) (yellowish white)

Double replacement reactions In such reactions, the two reacting ions are exchanging mutually, forming new compounds.

Neutralization It is the reaction of an acid with an alkali forming salt and water. Acid + alkali salt + H+Cl- + Na+OHNa+Cl+

12

water H2O


: Double replacement among salt solution NaCl

+

AgNO3

NaNO3

+ AgCl (white ppt)

The precipitate means that salt is not dissolved in water.

Advantage of chemical reaction in our life It is produced a thousands of compounds are commonly used in many industries such as medicines, fertilizers, fuel, plastics and others.

Disadvantage of chemical reaction in our life Fuel burning is an example for environmental pollution such as: 1. Carbon dioxide: It increases the atmospheric temperature where it acts as a green house. 2. Carbon monoxide: It has a dangerous impact on the human beings, that it causes headache, fainting in addition to serve stomach aches and may lead to death. 3. Sulphur dioxide and sulphur trioxide: They are acidic gases causing malfunctions in respiratory system of livings and corrosion of buildings. 4. Nitrogen oxides: They are resulted at the time of lightning. They are poisonous, and they are acidic gases that affect the nervous system and the eye. 5. Burning of coal and cellulose fibers such as paper and cigarettes causing air pollution and lung cancer.

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Lesson (3)

I.

Write the chemical equation representing the following reactions, and then indicate the type of each reaction:

a. Heating copper carbonate. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b. Hydrochloric acid reacts with ammonia gas. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c. Carbon burning in the presence of oxygen. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… d. Hydrochloric acid reacts with sodium hydroxide. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

II.

Define each of the following:

a. Neutralization reaction. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b. Endothermic reaction. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c. Exothermic reaction. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… d. Chemical reaction. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… e. Chemical equation. …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

III.

From the following equation 2Mg

+

O2

Δ

2MgO

If the mass of Mg = 24 and O =16, calculate the mass of reactants and products. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 14


IV.

Compare between each pair of the following :

a. Exothermic and endothermic reactions Exothermic reactions

Endothermic reactions

b. Direct combination and double substitution reactions Direct combination

V.

Double substitution

Give reasons for:

a. Chemical equation should be balanced. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b. A white precipitate is formed when NaCl solution reacts with AgNO3 solution. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c. The reaction of hydrogen with oxygen to form water is considered as an exothermic reaction. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… d. The reaction of nitrogen with oxygen to form nitrogen dioxide is considered as an endothermic reaction. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

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Unit 2 Force and Motion Lesson 1

Universal forces in nature Lesson 2

Accompanied forces with motion Lesson (3)

Wave motion

16


Unit 2 Force and Motion Lesson 1

Universal forces in nature

Force It is an effect attempts to change the object phase from being static to motion or vice versa, or attempts to change the motion direction. (Kicking a ball –Pushing objects)

Examples Types of Forces 1- Attraction forces.

2- Electromagnetic forces. 3- Strong nuclear forces. 4- Weak nuclear forces

First: Attraction forces 1- Earth's gravity force to objects: Earth attracts object to its center by a force known as the object weight, this force increases when the object's mass becomes larger. Object weight: It is the product of an

object mass X Earth's gravity acceleration

N.B. An object weight changes from one place to another on earth's surface. 2- Newton's general attraction law. Every two objects attract to each other by a force which is directly proportional to the product of the two object masses (M1 × M2) and inversely proportional to the square distance between the objects centers (d2). Newton's general attraction law =

M1 × M2 d2

17


Second: Electromagnetic forces 1- Electric force: Brush your hair fast for 10 seconds by a comb then approach it to small paper pieces. The comb attracts paper pieces, but they fall down after a while. WHY? When you rub the comb with your hair, a weak electric charge is generated making the comb able to attract small paper pieces which were not charged at the beginning. Some charges have been passed from comb to the paper pieces which are similar to those of the comb so the repulsion occurred and paper pieces fall down after a while. Objects with like charges repel whereas objects with unlike charges attract to each other Coulomb's law The attraction or repulsion forces between two charges are directly proportional to the product of the 2 charges (q1 Ă— q2) and inversely proportional to the square distance (d2). 2- Electromagnetic forces: The electric current has magnetic effect (ability to attract iron objects). Electromagnet: It is made up of an isolated copper wire coiling around a bar of soft iron. When electric current passes through it, it works as a magnet. The uses of electromagnet: 1- Electric winches.

2- Electric bell.

Electric generators: They are devices that convert the mechanical energy into electric energy (Dynamo). Electric motors: They are devices that convert the electric energy into mechanical energy.

18


Third: Nuclear forces The atom stores a massive amount of energy inside the nucleus. This massive energy is accompanied with forces known as nuclear forces which can be divided into:

1- Weak nuclear forces: It is used to get radioactive elements and radiation used in medicine, in scientific researches and in industry.

2-Strong nuclear forces: It is used in producing electric energy and in military purposes (Atomic bomb).

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Lesson (1)

I.

Define each of the following:

1- Force. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2- Weight. …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

II.

Mention each of the following:

1- Newton's general attraction law. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2- Coulomb's law . …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

III.

Give reasons for:

1- Gravity acceleration varies on earth's surface from place to another. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2- An object weight is not the same from place to another. …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

IV.

Compare between each pairs of the following:

1- Weak nuclear forces and strong nuclear forces. Weak nuclear forces

Strong nuclear forces

20


Lesson 2

Accompanied forces with motion

Inertia It is the property of an object to resist the change of its phase from rest to motion in regular speed and in straight line unless an external force acted upon it.

Examples 1- Passengers rushed forward when the bus stops suddenly . 2- Football player rushed forward and falls down if tripped during running . 3-Throwing solid objects from a moving car, object falls down and continues running . Safety belts and inertia forces: The safety belts work on stopping the forces of inertia, to protect passengers in cars or planes, when a sudden change in motion occurs.

Centrifugal force It is generated when objects move in circular paths.

Examples I. Cars moving in circles in the park . II. Motorcycle rotating in a cage.

N.B. 1-The centrifugal force which affects an object increases when the object speed increases. 2-Centrifugal force is directly proportional to the square of the speed .

Friction Friction generates a force against the motion to resist it.

Examples Brakes decrease the speed of cars, bikes etc‌..

21


Benefits of friction: 1- It prevents feet from slipping on road during walking. 2- It helps to slow, to stop and start car's motion. Harms of friction: I. It causes a great loss of mechanical energy because this energy is changed into heat energy. II. Generated heat due to friction causes some parts of machines to get hot; in addition this heat causes expansion of these parts so it affects their performance. III. It causes the errosion of machines parts.

Forces inside living systems There are forces inside living systems which enable living organisms to do their different biological operations such as: I. Heart muscle contraction and relaxation. II. Pulse inside blood vessels. III. Liquids transport through pores and the walls of cells from the lower concentration to higher one. IV. The contraction and relaxation of muscles to move the body organs.

22


Lesson 2

I. Define each of the following: 1- Inertia. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2- Centrifugal force. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 3- Friction force. …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

II. Give reason for each of the following: 1- The car passengers are pushed forward when the car stops suddenly. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2- Lubricating and oiling mechanical machines. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 3- Traffic signs are placed where roads are curved referring to reduce speed. …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

III. Mention two benefits and three harms of friction forces : …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

IV. Mention the forces inside living organisms : …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

23


Lesson (3)

Wave motion

Relative motion Change an object position or its direction with time passes in proportion to another object and in proportion to a fixed point known as a frame of reference.

Examples When you drive a car in the street then you stop, watching other moving cars give you a feeling that your car is moving although it is in rest.

Types of motion A- Periodic motion: It is a motion which is regularly repeated in equal periods of time .

Examples 1- Vibrating motion: such as the pendulum. 2- Circular motion: such as fan arm. 3- Wave motion: such as water waves. B- Transitional motion: It is the motion in which the object position is changed in proportion to a fixed frame of reference from time to time from an initial position to final one.

Examples The train and bike motion.

Applications on wave motion Lightning and thunder: We see lightning before hearing the thunder because thunder sound transfers in a form of mechanical waves but lightning flash transfers in another type of waves known as electromagnetic waves. 24


Types of waves Mechanical waves   

Vibration of medium particles. They need a medium to transfer through. Their speed is relatively low.

 

Examples: Sound waves. Water waves.

Electromagnetic waves   

They are accompanied with electromagnetic forces. They spread out in all media and space. Their speed are extremely great and can be accounted as: 300 million m/s

Examples: Light waves – radio and TV waves – ultra violet – infrared rays

Some technological applications for mechanical waves 1- Examining and curing sets for human body using sound waves. 2- Stringed musical instruments such as violin, lute and guitar. 3- Pneumatic musical instrument such as flute and the reed pipe. 4- Amplifiers and sets of distributing and controlling sound used in broadcasting studios. Some technological applications for electromagnetic waves 1- Applications for infra red rays: Night vision – remote sensing – cooking food – making remote sets. 2- Applications for ultraviolet rays: Sterilizing the sets of surgical operations rooms. 3- Applications for X-rays: Photographing bones – examining mineral raw in industry. 4- Application for gamma rays: It is used in medical purposes such as treatment and discovering some swellings. 5- Visible light: It is used in photographic cameras, Television cameras and data show.

Graphing motion When an object moves in straight line, the displacement occurred to the object changes with the time passes from the object original position.

25


1- If the displacements occurring every second are equal, it is called uniform velocity, and it is represented as follow:

Regular speed motion

Displacement

Time

2- If the displacements occurring every second are not equal, it is called non- uniform velocity.

Irregular speed motion

Displacement

Time

3- If the displacement value is fixed (it doesn't change with time passing), it is said that the object is in static state.

Displacement

Time

Displacement: It is the distance at which an object moves away from its original position at any moment. 26


Lesson (3)

A. Define each of the following: 1- Relative motion. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2- Transitional motion. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 3- Periodic motion. …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

B. Compare between each pair of the following: 1- Periodic motion and transitional motion. Periodic motion

Transitional motion

2- Mechanical waves and electromagnetic waves. Mechanical waves

Electromagnetic waves

C. Complete the following table: Technological applications

Rays used

Night vision Cooking food Sterilizing the sets of surgical rooms Photographing bones Medical purposes

27


Unit 3 Earth and universe Lesson 1

Celestial bodies Lesson 2 The earth Lesson 3 Rocks and minerals Lesson 4

Earthquakes and volcanoes

28


Unit 3 Earth and universe Lesson 1

Celestial bodies Stars, planets, moons, and rocky or gaseous bodies which rotate in the space.

The light year The distance covered by the light in a year = 0.467Ă—1012 Km.

Galaxies They are the biggest units that compose the universe. The galaxy that our solar system belongs to is known as (The way of chopped hay) or (The Milky Way).

Solar system

The sun

Planets

Moons

Asteroids

29

Comets

Meteors

Meteorites


Planets Eight spherical bodies revolving around the sun (anti clockwise) in elliptical path.

Moons Small planets rotating around the large ones due to gravity. Planet

No. of moons rotating around it

Mercury

None

Venus

None

Earth

1

Mars

2

Jupiter

62

Saturn

60

Uranus

27

Neptune

12

Asteroids They are thousands of different sized rocky masses. Most of them rotate between the two orbits of Mars and Jupiter in a certain region known as the wondered asteroids belt which separates the outer from the inner planets.

Comets It consists of head and tail. A- Head which contains : 1- Ice spheres contain (CO2 – N2 – methane). 2- Rocky parts (dust – water molecules). B- Tail which consists of gaseous clouds. The most famous comet is Halley.

Meteors Small rocky masses that fall within the atmosphere and burn due to the heat of friction, they appear as luminous arrows that can be seen with the naked eye. 30


Meteorites Huge solid rocky masses that fall and didn’t burn completely as they penetrate the atmosphere. The biggest meteorite till now has a mass of 80 tons and exists at the southern west of Africa. Arrangement of planet according to the distance away from the sun : Mercury – Venus – Earth – Mars – Jupiter – Saturn – Uranus – Neptune

Classification of planets Points of comparison

Inner planets

Outer planets

Size Density Surface Atmosphere

Small High (3.3 to 5.5 gm/cm3) Solid They have atmosphere except Mercury They have few numbers Mercury – Venus – Earth Mars

Big Low (0.7 to 1.3 gm/cm3) Gaseous They haven’t atmosphere

No of moons Names

They have large numbers Jupiter – Saturn – Uranus – Neptune

Isaac Newton proved that there is a force of gravity between any two objects in the space. This force of gravity depends on the mass of the two objects and the distance between them. Planet

Force of gravity on the surface (m/s)

Mercury

3.78

Venus

8.60

Earth

9.78

Mars

3.72

Jupiter

22.88

Saturn

9.05

Uranus

7.77

Neptune

11.00

31


Telescope It is an instrument used to identifying the celestial bodies. Types of telescope: 1- Reflecting

2- Refracting

32


Lesson 1

I.

Define each of the following:

1-Asteroids: ………………………………………………………………………………………..…………………… …………………………………………………………………………………………………………….. 2-Meteors: ………………………………………………………………………………………..…………………… ………………………………………………………………………………………..…………………… 3-Meteorites: ………………………………………………………………………………………..…………………… ………………………………………………………………………………………..…………………… 4-Comets: ………………………………………………………………………………………..…………………… ………………………………………………………………………………………..……………………

II.

Complete the following table

Points of comparison

Inner planets

Outer planets

1-Planets names

2-Distance from the sun

3-Composition

4-Density

III.

Give reasons for:

a-The density of outer planets is low. ………………………………………………………………………………………..…………………… ………………………………………………………………………………………..…………………… b-The gravity on earth’s surface is larger than that on Mars surface. ………………………………………………………………………………………..…………………… ………………………………………………………………………………………..…………………… C-Astronomers do not measure the distance between the planets by kilometers. ………………………………………………………………………………………..…………………… ………………………………………………………………………………………..…………………… 33


Lesson 2

The earth Earth location within the solar system The earth occupies the third location among the planets, it lies between Mercury and Venus. The distance between the earth and sun is about 150 million kilo meters.

Earth shape I. It is a spherical object flattening at the two poles and indented at the equator. II. The tropical radius increases 22 km than the polar radius. III. Earth occupies the fourth order regarding to the volume, its average radius is about 6368 km.

Earth mass Earth is considered as having the biggest mass in the inner planets; its mass is 5.9 X 1024 Kg.

Reasons causing life to continue on earth 1 - Atmosphere Group of gases surrounding the earth causing living to breath, protecting them from harmful radiations.

Importance of atmosphere 1 – It consists of several gases mixed together in definite ratio. Gas

Ratio

Importance

nitrogen

Oxygen

21 %

Respiration of livings Burning process

oxygen

Nitrogen

78 %

Decreases the effect of oxygen Formation of proteins

Carbon dioxide

0.03 %

Photosynthesis process

Water vapour

Variable %

-

Other gases

Very little %

-

34

carbon dioxide

water vapour and other gases


Other importance for earth’s atmosphere 1 – Burning of meteors before reaching earth’s surface. 2 – Decreasing the speed of meteorites. 3 – Climate phenomena. 4 – Keep suitable temperature on earth. 5 – It contains the ozone layer’s protecting livings from U.V. dangerous radiation.

2 – Earth’s hydrosphere Water represents 71 % of the earth’s surface.

Water

Salty water 97 %

Fresh water 3 %

Underground water which exists in the pores of rocks

Importance of water for living organisms 1 – Photosynthesis process. 2 – Completion of food digestion and absorption. 3 – Blood formation and keeping the body temperature constant. 4 – Keeping temperature on land during day and night within proper limits. 5 – Suitable environment for aquatic living organisms.

land water

salty water fresh water

3 – Suitable temperature The presence of earth in the third order far from the sun makes the temperature suitable for the continuity of living organisms.

4 – The gravity 1 - Helps in fixing objects and living organisms on its surface. 2 – Fixing the hydrosphere on its surface. 3 – Keeping the earth surrounded with the atmosphere. 5– The suitable atmospheric pressure. Atmospheric pressure equal 76 cm ∕ Hg. 35


The inner structure of earth

The crust 5 – 40 km

The mantle 2885 km

The core

Inner core 1216 km

36

Outer core 2270 km


Lesson 2 I.

Mention the importance of water for living organisms

a-…………………………………………………………………………..……………………………… b-…………………………………………………………………………………………………..……… c-………………………………………………………………………………………………………….. d-…………………………………………………………………………………………………………..

II.

Compare between the inner and outer core Points of comparison

Inner core

Outer core

Thickness State

III.

Give reasons for:

a - Temperature on earth’s surface suits the life of living organisms. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b - Earth’s inner core is solid. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c - Steadfastness of the hydrosphere on earth’s surface. ………………………………………………………………………………………..…………………… ……………………..………………………………………………………………………………………

IV.

Explain briefly the importance of:

a-Oxygen gas. 1-…………………………………………………………...……………………………………………... 2-………………………………………………………………………………………...………………... 3-………………………………………………………………………………………………………….. b-Carbon dioxide gas. 1-……………………………………………………………………………...…………………………... 2-………………………………………………………………………………...………………………...

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Lesson 3

Rocks and minerals

Classification of rocks

( Igneous rocks )

(Sedimentary rocks)

(Metamorphic rocks)

Formed from the molten material which exist underneath earth’s crust

Form a thin cover that wrap about 75 % of the earth’s solid surface, it represents 5 % only of earth’s crust rocks

Originated as a result of exposing the old rocks to high pressure and temperature

(Plutonic igneous rocks)

(Volcanic igneous rocks)

Formed inside earth’s crust at great depths

Formed when the magma reaches earth’s surface

Ex: granite

Ex: basalt

Ex:

(Sand stone )

(Lime stone)

Yellow color Coarse textured Thin layers

White color Smooth touch

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marble


Granite I. Its color is pink or grey, it exists in the eastern desert and Sinai Peninsula. II. It is heavy rough, solid cohesive and hard breakable. III. It consists of three main minerals which are quartz, feldspar and mica.

Basalt I. It exists in abu-zaabal and close to abu-rawash and faiyoum. II. It is a dark colored rock. III. It consists of olivine and pyroxene. Granite

Quartz

Feldspar

Mica

Basalt

Pyroxene

Olivine

Sandstone

Limestone

Marble

Basalt

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Lesson 3 I.

What are the main factors that lead to the formation of the metamorphic rocks?

…………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

II.

What is meant by?

a-Igneous rocks: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b-Sedimentary rocks: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c-Metamorphic rocks: …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

III.

Give an example for each of the following:

a-Plutonic igneous rock (……………………….………) b-Volcanic igneous rock (………………………….……) c-Sedimentary rock (………………………….…….) d-Metamorphic rock (……………………………….)

IV.

Mention the main minerals that share in the structure of the following rocks:

a-Granite …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… b-Basalt …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… c-Limestone …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

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Lesson 4

Earthquakes and volcanoes

Earthquakes Rapid and successive shaking of the ground, takes place one after the other.

Causes of earthquakes 1-The breaking of rocks suddenly due to the fractures in rocks of earth’s crust called fault. 2-Volcanoes.

The fault It is a fracture in earth’s crust which causes the sliding of rocks

Fault with horizontal displacement

Fault with vertical displacement

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Earthquakes intensity Varies from unfelt smooth shakes to extremely violent ones. Seismograph structure: as shown in the figure

Idea of operating When an earthquake occurs, the waves shake the ground, so the cylinder is also shaked, where is the metallic weight remains steady therefore, the pencil draw a zigzag line, called the seismic record on the paper.

The unit of measuring the intensity of earthquake Richter.

Harms of earthquakes 1-Losses in spirits and buildings. 2-Roads blocking, dams destroying and occurrence of fires. 3-Extremely high waves (Tsunami) which destroy and submerge coastal cities.

Benefits of earthquake Studying of the internal structure of the earth.

The volcano It is an opening in the earth’s crust which allows the passage of molten materials (lava) and gases outside it to the earth’s surface.

Parts of volcano 1-volcanic vent: An opening at the top of volcano. 2-The pipe or neck: It is a cylindrical cavity which reaches the earth’s surface. 3-The cone: It is the body of volcano.

The materials ejected during the volcanic eruptions materials: A-Fragmented The materials that the volcano emanates them. B-Lava and lava flow: Molten materials that spread out of the volcano. C-Volcanic gases: Water vapour, oxides of carbon, nitrogen and sulfur. 42


Harms of volcanoes 1- Lava and lava flows cover whole towns and villages. 2- Emission of harmful gases and dust. 3- Fire catches the cultivated lands and neighboring places.

Benefits of volcanoes 1-Production of electricity. 2-Increase the fertility of the soil. 3-Formation of new islands in the sea. 4-Formation of volcanic rocks with great economic values.

Safety precautions at natural catastrophes A-At the time of earthquake: 1-Take a position under a hard table. 2-If you were outdoor, go away from the building. 3-If you were in the car, remain inside it. B-Directly after the earthquake: 1-Before you’re going out from home, cut out the electricity, gas and water. 2-Don’t enter buildings harmed by earthquake. 3-Listen to the radio to follow the instructions.

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Lesson 4 I.

Define each of the following:

A-Earthquake: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… B-Volcano: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… C-Vent: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… d-The cone: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… e-The pipe: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… F-Seismograph: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… G-Richter: …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

II.

Mention the benefits of each of the following:

A-Earthquakes: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… B-Volcanoes: …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

III.

Give reasons for:

1-Volcanic ash covers areas far away from the volcano. …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… 2-Earth shaking takes place at the occurrence of earthquakes. …………………………………………………………………………………………………………… ……………………………………………………………………………………………………………

IV.

What are the most important volcanic gases?

a-……………………………………………………..………………………………………………….. b-………………………………………………………………………..……………………………….. c-…………………………………………………………………………………………..……………..

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SCIENCE G 7 BOOKLET - SECOND TERM