Port Said International Schools
Revision sheet
grade: 8
Better Education for Future Generations
Science Department
Name: …………………………….
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Unit one
1)Complete the following:
1-Mendeleev arranged the elements in ascending order according to their…………….
2-The advantages of Mendeleev period table are………………….and…………….
3-Moseley arranged the elements in ascending order according to their…………….
4-Elements are classified in the Modern periodic table according to
…………………and…………………………….
5- Modern periodic table consists of ........horizontal periods and……..vertical groups .
6-The atomic size is measured by …………………
7- ……………….and……………….are examples of polar compounds.
8-Each period in Modern periodic table starts with ………….and ends with…………..
9-The kind of elements which precede the inert gas in each period is ………………..
10-Magnesium reacts with dilute acids and …………..gas evolved
11-Mg + 2HCl
…………+………………
12-Mg + O2
………………………..
13-MgO + H2O
………………………
14- CO2 + H2O
………………………….
15-Water molecule consists of……………of hydrogen and………..of oxygen.
16-The angle between the two single covalent bonds in water molecule is………..
17-There are ……………….bonds between water molecule.
18-When the water freezes its volume………………..and its density…………………
19-When acidified water decomposes by electricity………evolves above the cathode,
while ………evolves above the anode.
20-Metals oxides dissolve in water and form……………., while nonmetals oxides
dissolve in water and form…………….
---------------------------------------------------------------------------------------------------------------2)Choose the correct answer:
1- The atomic number for element (Z) which lies in group (2A) and period 3 is ………
( 12 - 6 - 20 - 18 )
2- The atomic size of the elements of the same period…………………..by increasing
their atomic number.
( increase - decrease - doesn't change )
3-By increasing the atomic number, the electronegativity of elements of the same
period………
( increase - decrease - doesn't change )
4-All of these elements metalloids except……………….
( silicon - sulpher - boron - arsenic )
5- Nonmetallic property of the same group…............ by increasing the atomic number.
( increase - decrease - doesn't change )
6- Metallic property of the same group…............by increasing the atomic number.
( increase - decrease - doesn't change )
7-The physical state of iodine (I) is ………………………..
( solid - liquid gas )
8- On the electrolysis of a certain volume of acidified water if the volume of evolved
gas at cathode is 8 cm3, so the volume of evolved gas at anode is…………cm3.
( 8
4
16
- 10 )
9-There are ………………bonds between the water molecules.
( hydrogen
- covalent
- ionic
- metallic)
10-Water has ………………effect on litmus paper.
(basic - acidic
neutral - alkaline)
11-Drinking water which contains high ratio of…………..leads to blindness.
( Mercury
- Lead
- Arsenic
- Sodium )
12-Each period in the modern periodic table ends with………………element.
(metallic – inert – semimetallic – nonmetallic)
13-Alkaline earth metals are considered ……………….block groups.
(s - p -d
-f)
14- Metals oxides are ………… oxide.
(acidic – basic – amphotoric – neutral)
3)Give reasons for:
1-Mendeleev left space (gaps) is his table.
…………………………………………………………………………………………
…………………………………………………………………………………………
2-Some covalent compounds as sugar dissolve in water.
…………………………………………………………………………………………
………………………………………………………………………………………
3-Water has high boiling point.
…………………………………………………………………………………………
…………………………………………………………………………………………..
4-Water has low density when it freezes.
…………………………………………………………………………………………
…………………………………………………………………………………………
5-Water used in fire extinguishing.
………………………………………………………………………………………………………
……………………………………………………………………………………………………..
6-Pure water has a neutral effect on both litmus paper.
…………………………………………………………………………………………
…………………………………………………………………………………………
7-The atomic size of the elements of the same period decrease by increasing their
atomic number
…………………………………………………………………………………………
…………………………………………………………………………………………
8- The atomic size of the elements of the same group increase by increasing their
atomic number
…………………………………………………………………………………………
…………………………………………………………………………………………
9-Alkali metals are kept under kerosene.
………………………………………………………………………………………….
…………………………………………………………………………………………
10-Halogens are monovalent nonmetals
…………………………………………………………………………………………
…………………………………………………………………………………
11-Alkaline Earth metals are divalent elements
…………………………………………………………………………………………
……………………………………………………………………………………
12-Natural elements in group (17) don't exist individually.
…………………………………………………………………………………………
……………………………………………………………………………………
13-Silicon slides are used in manufacture of computers.
…………………………………………………………………………………………
…………………………………………………………………………………………
14- Liquefied nitrogen is used in preservation of the cornea of the eye.
…………………………………………………………………………………………
………………………………………………………………………………………….
15-Liquified sodium is used in transferring heat from inside the nuclear reactor to
outside.
…………………………………………………………………………………………
…………………………………………………………………………………………
16- Elements of the same group have similar properties.
…………………………………………………………………………………………..
4) What is meant by:
1. Chemical activity series.
……………………………………………………………………………………………
2. Atom.
……………………………………………………………………………………………….
3. Positive ion.
……………………………………………………………………………………………......
4. Metalloids.
………………………………………………………………………………………………..
5. Nonmetals.
……………………………………………………………………………………………….
6. Electro negativity.
………………………………………………………………………………………………..
7. Polar compounds.
………………………………………………………………………………………………
8. Ionization process.
………………………………………………………………………………………………..
5) Locate the position of the following elements in the modern periodic table:
1. 4Be …………………………………………………………………………………
2. 12Mg ………………………………………………………………………………..
3. 20Ca …………………………………………………………………………………
6) Write the contribution of the following scientists :
1- Mendeleev…………………………………………………………………………………….
2- Rutherford………………………………………………………………………………………..
Moseley……………………………………………………………………………………………………………………………………………
4- Bohr……………………………………………………………………………………………………………………………………………………
3-
7) Write the balanced chemical equations for the following reactions:
1. Burning of magnesium strip in oxygen
………………………………………………………………………………………………………………………………………………….
2. Magnesium with hydrochloric acid
………………………………………………………………………………………………………………………………………………....
3. Burning coal in air
………………………………………………………………………………………………………………………………………………….
4. Carbon dioxide with water
………………………………………………………………………………………………………………………………………………….
5. Dissolving magnesium oxide in water
………………………………………………………………………………………………………………………………………………….
Unit two & three
1)Complete the following:
1-The measuring unit of the atmospheric pressure is ………………………..
2-The surface area at which the temperature is constant between troposphere and
stratosphere is known as ……………….
3-The temperature …………as going up in troposphere layer until it reaches………
4- Ionosphere is surrounded by two magnetic belt known as………………………..
5-The satellites float around the Earth in an area known as…………………..where the
atmosphere is inserted into outer space.
6-The air movement in troposphere is……………while the air movement in
stratosphere is …………………….
8-…………………..are from the pollutants of ozone layer which are used in fire
extinguishers.
10-…………………is from the pollutants of ozone layer which is used as insecticide
to preserve stored agricultural crops.
11-The most important greenhouse gases are …………, ……………. and…………….
12-Examples of a complete body fossil are…………………..and………………….
13-………………. & ……………………… are examples of petrified fossils.
14- Studying the fossil record showed that the first vertebrate appeared was ………..
15-Archaeopteryx represents the link between ……………..and……………….
16-From factors causing extinction of species are …..........,………and ……………….
2) Choose the correct answer:
1-The atmospheric pressure……………as we rise up above the sea level.
(increases
decreases
- doesn't change )
4- All the following are greenhouse gases except……………
(CO2
- O2
- N2O
- CH4 )
5-Ozone layer is measured by a unit called……………
( km
nm
Dobson
- mm3 )
6-Most of the weather features occur in ………….layer
(troposphere
- thermosphere
- mesosphere - stratosphere )
7-……………..are used in extinguishers
(methyl bromide gases
- halons
- nitrogen oxides - UVradiation)
8-The scientists have noticed there was erosion of ozone layer above…………..
( north pole - south pole - equator )
9-When CFC compounds breaks down under the effect of UV radiation ……….atom
liberates.
(chlorine fluorine - carbon - oxygen )
10-…………………is from the endangered animals because of global warming.
( Blue whale - seal - shark )
11-The movement of air is vertical in …………layer.
(troposphere - stratosphere - mesosphere - thermosphere )
12-fossils are often found in ………………….rock.
( metamorphic - sedimentary - volcanic - igneous )
13-……........fossils, they indicate that the environment where they lived was a hot and
rainy tropical environment.
( Nummulites - Ferns
- Coral )
14-……........fossils, they indicate that the environment where they lived was clear,
warm and shallow seas.
( Nummulites - Ferns
- Coral )
15- -……........fossils, they indicate that there was a sea floor in Gebel Mokattam.
( Nummulites - Ferns
- Coral )
16- Complete fossils of insects are found preserved in………………………
(ammonites - amber - igneous rock - metamorphic rock )
17-………………. is a replica of the internal details of an ancient organism.
(Mold – Cast – Trace – Petrified fossil)
18- ………………. is a replica of the external details of an ancient organism.
(Mold – Cast – Trace – Petrified fossil)
3) Give reasons for:
1- Ionosphere is important for radio stations..
………………………………………………………………………………………………………
……………………………………………………………………………
2-The lower part of the stratosphere is suitable for flying airplanes.
……………………………………………………………………………………………………….
………………………………………………………………………………………………………
3-The phenomenon, ozone hole, increases in September each year.
………………………………………………………………………………………………………
……………………………………………………………………………………………………..
4- Stop building concord airplanes.
………………………………………………………………………………………………………..
………………………………………………………………………………………………………
5 Mesosphere layer is much vacuumed.
………………………………………………………………………………………………………
………………………………………………………………………………………………………
6- Bald eagle is from endangered species.
………………………………………………………………………………………………………
……………………………………………………………………………………………………..
7- Hunting of Tasmanian cat by peasants.
………………………………………………………………………………………………………
……………………………………………………………………………………………………..
8- Disappearance of papyrus plant from upper Nile.
………………………………………………………………………………………………………
……………………………………………………………………………………………………
4)Write the word(s) that means each of the following statements:
1- The continuous increase of the average temperature of the air near the surface of the Earth.
(
)
2- The weight of air column of an atmosphere height above a unit area. (
).
3-One of the atmosphere components that its ratio increases in recent years to reach 0.038%
(
)
4-An extinct bird has short legs and its wings are small.
(
)
5- An extinct bird ,its female lays only one egg each spring and its extinction due to cutting the oak
and beech trees
(
)
6- An extinct mammal, midway between horse and zebra.
(
)
7- An extinct mammal has a wolf's head, dog's tail, a pouch like kangaroo and striped skin like a
tiger.
(
)
8-An endangered mammal , it inhabits Bamboo forests in northeast China. (
)
9- An endangered mammal, it overhunted for using its horn for medical purposes. (
)
10- An endangered bird , its head covered with white feathers.
(
)
11- An endangered bird, it disappeared from Aswan after the building of the High Dam (
)
12- An endangered plant, it grow in swamps of the Upper Nile, it was used to manufacture writing
papers.
(
)
5)Choose from column(B)what suit in column(A):
A
1-Troposphere
2-Mesosphere
3-Stratosphere
4-Mesopause
5-Exosphere
6-Ionosphere
B
a- the hottest layer in the atmosphere envelope.
b- it is the region in which the atmosphere envelope is inserted with the
outer space.
c- it is the region between mesosphere and stratosphere.
d- it is the layer in which air moves horizontally.
e- the coldest layer in the atmosphere envelope.
f- the layer that all atmospheric phenomena happen in it.
g- it has an important role in wireless communications .
h- it is the region mesosphere and thermosphere.
6)Problem:
1-Calculate the height of a mountain if the temperature at its base 25oC and its top -14oC
………………………………………………………………………………………………………
………………………………………………………………………………………………………
……………………………………………………………………………………………………….
2- Calculate the temperature at a point of height 2 km above the sea level if the temperature ate sea
level is 24° C.
………………………………………………………………………………………………………
………………………………………………………………………………………………………
……………………………………………………………………………………………………….
7) What is meant by:
1- Atmospheric pressure?
…………………………………………………………………… ……....
2- Aurora phenomenon?
…………………………………………………………………………….
3- Exosphere region?
…………………………………………………………………………….
4- Ionosphere?
…………………………………………………………………………….
5- Global warming?
……………………………………………………………………………
6- Greenhouse effect?
…………………………………………………………………………
8-Fossils
…………………………………………………………………………………………..
9- Extinction
…………………………………………………………………………………………...
10- Simple ecosystem
…………………………………………………………………………………………
11- Complicated ecosystem
…………………………………………………………………………………………
12- Natural protectorate
…………………………………………………………………………………………..
8) Mention the importance of :
1.
2.
3.
4.
5.
6.
Aneroid: …………………………………………………………………….………..
Altimeter: …………………………………………………………………………….
Ozone layer: ………………………………………………………………….………
Van Allen belts: …………………………………………………………..………….
Satellites: …………………………………………………………………….........
Halons: …………………………………………………………………………..
7. Fern fossil: ……………………………………………………………………………
8. Coral fossil: …………………………………………………………………………..
9. Nummulities fossil: …………………………………………………………………..
10. Radiolaria fossil: …………………………………………………………………..
11. Hoffman voltmeter: ………………………………………………………………
9) Look at the next figure then answer:
1- Label the next figure.
10) Look at the next figure then answer:
1- Label the next figure.
(2)
(1)