Misr language school
Second preparatory
Model Answer for general exercises
In school book
Pages 111, 112:
Choose the correct answer:
1- Alkaline earth metals
3- Mesosphere
2- Halogens.
4- Overhunting and environmental pollution.
Write the Chemical equations representing the following:
1- MgO + H2O
= Mg(OH)2
2- Cl2 + 2KBr
= 2KCl + Br2
3- 2H2O = 2H2 + O2
Mention one difference between each of:
1- Fluorine molecule: group 7A, helium molecule: group zero
2- Natural pollutants: it causes by nature (volcanic eruption )
Industrial pollutants: it causes by human (chemical pollution: throwing
wastes of factories).
3- Troposphere: air pressure = 100 mb, Stratosphere: air pressure = 1 mb
4- Simple ecosystem: few members (Desert), Complicated ecosystem:
multiple members (forests)
Give reasons:
1- Due to the difference in electronegativity between its elements is
relatively high.
2- To prevent its reaction with moist air
3- The air moves horizontally and no weather conditions
4- Because it feeds on poisonous fish
Write brief notes on:
1- Water has a maximum density at 4oC, while water has a lowest density
at zero C.
2- As the height increases the atmospheric pressure decreases
3- It is a continuous increase in a temperature of earth's atmosphere due
to increase in a ratio of greenhouse gases.
To who are these works attributed:
1- Rutherford
2- Van- Allen belts
3- IUCN
Pages 113, 114:
Complete the following statements :
1- Ascending
2- Protons
3- Monovalent
4- 7A
Choose the correct answer for each of the following:
1- 116
2- number of protons
3- B, C are correct
4- Less than its density in liquid state
5- All the previous
Mark ( ) or ( x ) :
1- Right
2- False
3- Right
4- Right
5- False.
Write the scientific term :
1- Troposphere
2- Fossils (practical)
4- Negative ion
5- Hydrogen bonds.
3- Metalloids
Pages 115, 116 , 117 , 118 , 119 ,120 and 121 :
Choose the correct answer:
1- Group
2- Mendeleev 3- S
4- Transition 5- Bohr
6- Na, Li
7- Rutherford.
8- Inert gas
9- 7 10- Basic, Amphoteric then acidic .
11- Basic
12- Alkaline
13- Group 1A
14- Barium
15- Thermosphere
16- Mesosphere
17- Stratosphere
18- Barometer
19- Troposphere
20- Altimeter
21- Stratosphere
22- Ionosphere
23- Mesosphere
24- Mesosphere
25- 13 C
26- Weight
27- Mesosphere
28- Thermosphere
29- horizontally
30- Magnetic
31- Is less than
32- 1013.25
33- Troposphere
34- Stratosphere
35- Stratosphere
36- Three oxygen atoms
37- Ultraviolet rays
38- The south pole
39- Halons
40- Chloride
41- Nothing above
42- A and b
43- Infrared rays
44- September
45- Freon
46- Methyl bromide gas
47- Nitrogen oxides
48- A and b together
49- b and c
50- Dobson
51- all the above
52- Polar bears
53- Practical
54- Practical
55-Practical
56- Practical
57- Practical
58- Practical
61- Practical
64- Practical
59- Practical
62- Practical
65- Practical
60- Practical
63- Practical
66- The continuous decrease in number of individuals of the same species
without compensation
Pages 121 , 122 and 123 :
Complete the followings:
1- Rutherford, Moseley
2- Lanthanides and actinides
3- Transition elements
4- fourth
5- 7 and 18
6- Increases
7- Decreases
8- Metal, noble gas
9- 7A (17)
10- 13 km
11- Decreases, 6.5oC
12- 1013.25
13- Measure the atmospheric pressure with day weather.
14- 37 km
15- UV rays, oxygen molecule, oxygen molecule
16- UVA, UVB, UVC.
17- Skin cancer, cataract, and weakness of immune system
18- Spoil eggs, decrease rate of reproduction.
19- Death of plankton, destroy food chain.
20- Upset photosynthesis process, decrease crops production.
21- a) Oxygen molecule of oxygen atoms .
b) Oxygen molecule.
22- CFC, Halons, Nitrogen oxides
23- Methyl bromide gas
24- Visible light, UV rays
25- Reduce the use of CFC compounds; stop producing the ultra sound
Concorde planes
26- Continuous increase in temperature of earth's atmosphere
27- 10 -9 meters
28- UV rays, visible light
29- Earth's day
30-
38 practical
39- Number, certain, compensation, die
40- Practical
41- Global warming, Extinction
42- Overhunting, reptiles, mammals.
43- 1) Mesosphere, 35 km, hydrogen and helium.
2) Second, 37 km, ozone gas.
3) Thermosphere, fourth, charged ions (ionosphere)
Pages 123 , 124 , 125 :
Put ( ) or ( x ) :
1- Right
2- False, vertical groups.
3- False, ascending
4- Right.
5- Right
6- Right.
7- Right
8- False, B
9- False, 116
10- Right.
11- Right
12- False, 1.7
13- False, difficult
14- False, strong metal.
15- Right
16- Right.
17- Right
18- False, troposphere.
19- Right
20- Right.
21- 1013.25 miilibar
22- Right.
23- Right
24- False, second
25- Right
26- Right.
27- Right
28- Right.
29- False, stratosphere
30- False, horizontally.
31- Right
32- False, Dobson.
33- Right
34- Right.
35- Right
36- False, near only.
37- Right
38- False, nitrogen oxide
39- False September
40- False, Halons
41- Right
42- Right.
43- False, methane and CO2
44- Right.
45- False, 20 to 40 Km
46- Right.
47- Right
48- Right.
49- Right
50- Right.
Pages 125 , 126 ,127 , 128
Correct the underlined words:
1- Moseley
2- Bohr
3- Increase in atomic no.
4- Decreases
5- Noble gas
6- 7 group ( 7A ).
7- Acidic oxides
8- Second group.
9- Mammoth
10- Practical
11- Practical
12- Practical.
13- Practical
14- Practical.
15- Practical
16- Practical.
17- Practical
18- Practical.
19- Dinosaur
20- Quagga
21- Dodo bird
22- Endangered
23- Protectorates
Write the scientific terms:
1- Mendeleev's periodic table.
2- Moseley's periodic table.
3- Periods.
4- Groups.
5- Energy levels.
6- Sub levels
7- Transition elements.
8- P- block.
9- F - block.
10- Electronegativity
11- Amphoteric oxides.
12- Metals.
13- Non metals.
14- Group 7A
15- P- block.
16- Mesopause.
17- Thermosphere.
18- Altimeter.
19- Troposphere
20- Van Allen belts.
21- Aurora phenomena.
22- Mesosphere.
23- Exosphere.
24- Global warming.
25- Ozone gas.
26- Oxygen gas.
27- Infrared rays.
28- to 33 practical .
34- Extinction.
35- Overhunting.
36- Food chain.
37- Simple ecosystem.
38- Complicated ecosystem.
39- Protectorates.
Pages 128 , 129:
1- 1- c
2- a
3- e
4- b
6- f
2- 1- e
2- c
3- b
4- d
3- Practical.
4- 1- b ( practical ).
2- a ( practical).
3- d
4- e.
Page 130
Give reasons :
1- Because it has highest electronegativity and the largest atomic size non
metal.
2- Because it has the largest atomic size.
3- Because it dissolves in water forming acids , changing the colour of
litmus paper into red.
4- Because it dissolves in water forming bases , changing the colour of
litmus paper into blue.
5- Because it has both properties of acidic oxides and basic oxides .
6- Due to the attraction force between nucleus and the electrons in
outermost energy level increases.
7- Due to the difference in electronegativity between its elements is
relatively high.
8- Because the outermost energy level may be ends with 3 , 4 , 5 or 6
electrons.
9- Because it contains 75% of atmospheric mass .
10- Because it contains charged ions which reflect radio waves.
11- Due to 2 magnetic belts surrounds ionosphere.
12- Because it contains charged ions.
13- Because the ozone layer absorbs UV rays .
14- Due to pollutants which affects ozone layer such as CFC compounds ,
Methyl bromide gas , Halons and nitrogen oxides.
15- Because it protects earth from harmful UV rays
16- Because of cutting trees, burning fuels and burning forests.
17- To avoid erosion of ozone layer.
18- Practical.
19- Practical.
20- It causes extinction of more than 300 species.
21- Because it has a few members or alternatives.
22- It causes extinction.
23- Because it feeds on their sheep's and chickens .
24- Because it has short wings so it can't fly and short legs so it can't run.
25- Because of overhunting and changing its habitat to cultivated lands.
26- To protect the living organisms from extinction.
27- Because it has a large amount of skeletons of whales.
Page 131 :
What happens in the followings :
1- The colour changes into blue.
2- The colour changes into red.
3- It forms magnesium hydroxide.
4- The water molecule will be a non polar compound
5- It reaches maximum density
6- We cannot use it in putting off fires
7- It will change into water vapour
8- Water decomposes by electricity into hydrogen gas and oxygen gas .
9- It causes water pollution.
10- Practical .
11- Practical.
12- Practical .
13- Extinction of many species.
14- Extinct of passenger pigeons.
15- Disturbance in ecosystem.
16- Destroy natural habitat lead to extinction of species.
17- Extinct of passenger pigeons.
Page 131:
Compare between :
1- Alkalis: Group 1A, Monovalent; lose 1 electron during chemical
reactions.
Earth alkaline: Group 2A, Divalent; lose 2 electrons during chemical
reactions.
2- Group: elements have the same no. of electrons in outermost energy
level.
Period: elements have the same no. of energy levels .
3- Atomic volume ( size ) : distance between nucleus and the outermost
energy level.
Electronegativity: ability of an atom to attract the electrons in a covalent
bond toward itself
4- Altimeter: measure atmospheric pressure with height from sea level.
Aneroid: measure atmospheric pressure with day weather.
5- Troposphere: 100mb, decreases till it reaches – 60 C at its end.
Ionosphere: very low, increases till it reaches 1200oC at its end.
6- Mesosphere: 0.01mb, decreases till it reach – 90oC at its end.
Thermosphere: very low, increases till it reaches 1200oC at its end.
7- Atmospheric pressure: weight of air column over unit area
Atmospheric envelope: mixture of gases surrounds the earth and it
extends to 1000 kms
Pages 131 , 132:
Mention one difference:
1- Practical
2- Practical.
3- Practical.
4- Practical.
5- Simple ecosystem: few members
Complicated ecosystem: multiple members
6- Ras Mohamed: collection of coloured fish and coral reefs
Waadi Hetan: collection of skeletons of whales
Page 132 :
What is meant by:
1- Group of recommendations to protect ozone layer.
2- Chloro- fluoro carbon compounds
3- Intergovernmental panel on climate change.
4- Continuous increase in temperature of earth's atmosphere.
5- Standard Temperature and pressure.
6- Losing parts of ozone layer.
7- Measuring unit of ozone layer.
8- No Chloro fluoro carbon compounds
9- CO2, CH4, H2O and CFC compounds.
10- Lamps protect your environment and save your money.
11- Trapping infrared rays by plastic or galss.
12- Temperature = zero oC and Pressure = 1013.25mb.
13- 10-9 meters.
14- practical.
15- Practical.
16- Continuous decrease in number of living organisms of certain species
without compensation.
17- Practical.
18- List of endangered species and the level of danger of each species.
19- Practical.
20- Practical.
21- International union conservation of nature.
22- Practical
23- Practical.
Page 132:
What is the importance:
1- Scattering the harmful cosmic radiations away from earth.
2- Protecting earth from harmful UV rays.
3- Measure the atmospheric pressure with height from sea level.
4- Regulate the temperature of earth's atmosphere.
5- Wireless communications and radio stations.
6- Area in which satellites are rotating.
7- Transmit weather condition information and TV programs.
8- Measure the atmospheric pressure with day weather
9- Burning meteors before reaching earth.
Mention one example:
1- to 6 Practical.
7- Ibis bird.
8- Papyrus plant.
9- Dodo bird.
10- Passenger pigeon.
11- Panda.
Page 133:
Choose:
1- e
2- d
3- b
4- c
5- Ras Mohamed a.
6- No choices.
7- F (practical).
Model answer
Exam 1
Question one:
Complete the followings:
1- Properties.
2- Harmful
3- Dinosaur, mammoth.
4- Kerosene, moist air.
Question two:
Choose the right answer:
1- C
2- A
3- A
4- Practical
5- Practical
6- A
Question Three:
Give reasons for :
1- Due to its low boiling point – 196 C.
2- Because the air moves horizontally and no weather conditions .
3- Practical.
Question Four:
Put right or false:
1- false.
2- practical.
3- false.
4- right.
5- right.
6- right.
Model Answer
Exam 2
Question one:
A) Choose the right answer:
1- C
2- B
3- B
4- B
B) Element Y 17:
1- 2,8,7.
2- 7A
3- 3.
Question two:
A) Put true or false :
1- true.
2- true.
3- true in groups.
4- Practical.
5- true.
B) See the figure:
1- A
2- B neutral atom.
3- period 2 , group 2A.
Question Three:
Write scientific term:
1- Extinction.
2- Dodo bird.
3- Electronegativity.
4- Alkaline earth metals .
5- Natural protectorates.
Question Four:
Complete the followings:
1- bottom to up.
2- less , more.
3- stratosphere.
4- Practical.
5- halogens.
6- natural protectorates.
7- hydrogen .
8- Practical.