Science Department

2nd prep

General Revision

I.Complete the following statement :

  1. The scientist who discovered the presence of protons in the nucleus is ……………..
  2. All alkali metals are good conductors of ……………..and ……………..
  3. ……………..are instruments used for measuring atmospheric pressure and ……………..is used by pilots in airplanes to measure the-elevation from sea level.
  4. In group (17), the nonmetallic property of chlorine (17CI) is ………… than that of bromine (35Br).
  5. Elements of group (1) are known as ……………, while elements of group (17) are called ……………
  6. Ultraviolet radiation has a ……………effect, and the infrared radiation has a …………effect.
  7. …………………is the first layer of atmospheric envelope.
  8. …………………and …………………are endangered birds.

II.Put ( ) or ( ) and correct the wrong ones:

1 .Ozone gas molecule consists of three hydrogen atoms. ( )

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

2. Mendeleev arranged the elements in an ascending order according to their atomic numbers. ( )……………………………………………………………………………………………………

3. Elements of s-block are found on the left side of the modern periodic table.( )

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

  1. Atmospheric pressure decreases as we go up. ( )

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

  1. The atomic size increases in the same group by increasing the atomic number. ( )

……………………………………………………………………………………………………..

III.Write the scientific term:

  1. It is the ability of the atom in the covalent compounds to attract the electrons of the bond towards itself.
  2. Elements that have common properties of metals and non metals.
  3. Oxides that dissolve in water forming acidic solutions.
  4. The arrangement of metals in a descending order according to their chemical activities.
  5. It is used in food preservation as it produces gamma rays to stop microbes.
  6. The most metallic element.
  7. The scientist who discovered the main energy levels.
  8. The halogen which is found in the liquid state.

10.The curved lines that join between the points of equal pressure.

11.A phenomenon appears at poles as brightly coloured light curtains.

12.The continuous increase of the temperature of Earth.

13.They are traces and remains of old living organisms that are preserved in sedimentary rocks.

14.The continuous decrease of certain species of living organism until all members dies out.

IV.Give reasons for the following:

  1. Pilots prefer to fly their planes in stratosphere.

...…………………………………………………………………………………………………………

  1. Liquefied nitrogen is used in preservation of cornea of the eye.

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

  1. The atmospheric pressure decreases by increasing the altitude above sea level.

……………………………………………………………………………………………………..

  1. The metallic property increases in group (1A) by increasing the atomic number.

……………………………………………………………………………………………………..

V.Show by symbolic chemical equations:

  1. Reaction of potassium with bromine.

……………………………………………………………………………………………….

  1. Effect of bromine on potassium iodide solution.

……………………………………………………………………………………………….

  1. Reaction of sodium with water.

……………………………………………………………………………………………….

  1. Heating magnesium with oxygen and then dissolve the product in water.

………………………………………………………………………………………………

………………………………………………………………………………………………

VI.What is meant by each of the following:

1. Ionosphere

……………………………………………………………………………………………….

2. Atmospheric pressure.

………………………………………………………………………………………

VII.Choose the correct answer:

1. Transition elements appear starting from period ......

a.2 b.3 c.4 d.5

2. Burning of carbon in air produces ......

a. CO b. CO2c. HCI d. CuO

3 ……………is the third layer of atmospheric envelope.

a. Mesosphere b. Thermosphere c. Troposphere d. Stratosphere

4. The molecule of halogen is composed of ……………atom(s).

a.1 b.2 c.3 d. 4

5. The number of energy levels in the heaviest known atom is ……………levels.

a.5 b.7 c.8 d. 10

VIII.What is the importance of each of the following:

1. Silicon.

…………………………………………………………………………………………………………………………………………………………………………………………………………………..

2. Van-Allen belts.

…………………………………………………………………………………………………………………………………………………………………………………………………… …………….

IX.Mention the most important greenhouse gases.

…………………………………………………………………………………………………………………………………………………………………………………………………… ……………………….

X.What is the atomic number of an element which locates in period two and group (6 A)

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

XI.How can you differentiate between two pieces of sodium and silver, using water?

……………………………………………………………………………………………………..

……………………………………………………………………………………………………..

XII.Mention the most important factors that cause species extinction.

……………………………………………………………………………………………………..

……………………………………………………………………………………………………..

XIII.Compare between basic oxides and acidic oxides

Basic oxide / Acidic oxide

Science Department

2nd prep

Model answer

  1. Complete the following statement :
  1. The scientist who discovered the presence of protons in the nucleus is Rutherford
  2. All alkali metals are good conductors of heat and electricity
  3. Barometers are instruments used for measuring atmospheric pressure and Altimeter is used by pilots in airplanes to measure the elevation from sea level.
  4. In group (17), the nonmetallic property of chlorine (17CI) is higher than that of bromine (35Br).
  5. Elements of group (I) are known as alkali metals, while elements of group (17) are called halogens.
  6. Ultraviolet radiation has a chemicaleffect, and the infrared radiation has a thermal effect
  7. Troposphere is the first layer of atmospheric envelope.
  8. Bald eagle and ibis birdare endangered birds.
  1. Put ( ) or ( ) and correct the wrong ones:

1 . Ozone gas molecule consists of three hydrogen atoms. (  )

……………………………………………… oxygen ……………………………………

2. Mendeleev arranged the elements in an ascending order according to their atomic numbers. (  )…………………………………………………………………………atomic weight

3. Elements of s-block are found on the left side of the modern periodic table. (  )

4.Atmospheric pressure decreases as we go up. ( )

6.The atomic size increases in the same group by increasing the atomic number. ( )

  1. Write the scientific term:
  1. It is the ability of the atom in the covalent compounds to attract the electrons of the bond towards itself. (Electronegativity)
  2. Elements that have common properties of metals and non metals. (Metalloids)
  3. Oxides that dissolve in water forming acidic solutions.(Acidic oxides)
  4. The arrangement of metals in a descending order according to their chemical activities(Chemical activity series)
  5. It is used in food preservation as it produces gamma rays to stop microbes.(Cobalt 60)
  6. The most metallic element(Cesium)
  7. The scientist who discovered the main energy levels(Bohr)
  8. The halogen which is found in the liquid state(Bromine)

10.The curved lines that join between the points of equal pressure(Isobars)

11.A phenomenon appears at poles as brightly colored light curtains.(Aurora Phenomenon)

12.The continuous increase of the temperature of Earth(Global warming)

13.They are traces and remains of old living organisms that are preserved in sedimentary rocks.(fossils)

14.The continuous decrease of certain species of living organism until all members dies out.(Extinction)

  1. Give reasons for the following:
  1. Pilots prefer to fly their planes in stratosphere.

Because it does not contain clouds or any weather disturbances and the air moves in this part horizontally.

  1. Liquefied nitrogen is used in preservation of cornea of the eye.

Because of its low boiling point which equal (-196oc).

  1. The atmospheric pressure decreases by increasing the altitude above sea level.

Because by increasing the altitude the length of the air column decreases

  1. The metallic property increases in group (1A) by increasing the atomic number.

Due to the increase of the atomic size

  1. Show by symbolic chemical equations:
  1. Reaction of potassium with bromine.

2K + Br2 2KBr

  1. Effect of bromine on potassium iodide solution.

Br2 + 2KI 2KBr + I2

  1. Reaction of sodium with water.

2Na + 2H2O 2NaOH +H2

  1. Heating magnesium with oxygen and then dissolve the product in water.

2Mg + O2 2MgO

MgO + H2O Mg(OH)2

  1. What is meant by each of the following:
  1. Ionosphere:

It is a layer contains charged ions and it has an important role in wireless communication

  1. Atmospheric pressure.

It's the weight of air column of an atmosphere height per unit area (1m2)

  1. Choose the correct answer:

1. Transition elements appear starting from period ......

a.2 b.3 c.4d.5

2. Burning of carbon in air produces ......

a. CO b. CO2c. HCI d. CuO

3 ……………is the third layer of atmospheric envelope.

a. Mesosphere b. Thermosphere c. Troposphere d. Stratosphere

4. The molecule of halogen is composed of ……………atom(s).

a.1 b.2 c.3 d. 4

5. The number of energy levels in the heaviest known atom is ……………levels.

a.5 b.7c.8 d. 10

  1. What is the importance of each of the following:

1. Silicon.

A metalloid used in the electronic devices such as computers, because it is a semi-conductor.

2. Van-Allen belts.

Two magnetic belts surrounding the ionosphere layer,they scatter harmful charged cosmic radiations away from the earth.

  1. Mention the most important greenhouse gases.
    carbon dioxide – chlorofluorocarbon CFC - methane gas CH4 -Water vapour -nitrous oxide N2O
  1. What is the atomic number of an element which locates in period two and group (6 A)

(2, 6), so the atomic number is 8.

  1. How can you differentiate between two pieces of sodium and silver, using water?

Sodium reacts with water instantly and hydrogen gas evolves burning with pop sound, while silver does not react with water.

  1. Mention the most important factors that cause species extinction.

1-Destroying natural habitat 2-Overhunting

3-Environmental pollution 4-Climate changes and natural disasters.

  1. Compare between basic oxides and acidic oxides

Basic oxides / Acidic oxides
  1. They are metal oxides.
  2. They are formed by the reaction of metal with oxygen
  3. Some of them dissolve in water giving alkalis.
  4. Their solutions turn litmus paper into blue.
  5. Examples: Na2O & MgO
/
  1. They are non-metal oxides.
  2. They are formed by the reaction of non-metal with oxygen.
  3. They dissolve in water giving acids.
  4. Their solutions turn litmus paper into red.
  5. Examples: CO2 & SO2