للتواصل
(1)
1- Water is very important for living organisms
(2)
2- Water molecules are polar
(3)
3- Water has unique properties
(4)
4- Water is regarded as "the general solvent
(5)
5- Being water a polar solvent is very important to living organisms.
(6)
6- Water has the ability to ionize many molecules.
(7)
7- The ability of water to ionize many molecules is so important to livingorganisms.
(8)
8- Water has high specific heat.
(9)
9- High specific heat of water is important to us.
(10)
10- Waters of oceans absorb great amount of sunrays in the morning, andspreads them in atmosphere at night.
(11)
11- Water has low viscosity and high surface tension
(12)
12- The low viscosity and high surface tension of water are important to us.
(13)
13- Some insects can walk on water.
(14)
14- Water expands and its density decreases when its temperature becomes less than 4C
(15)
15- Water expansion at temp. less than 4C is important to living organisms.
(16)
16- The property of the decrease of the freezing point of water which containssolutes in very important to living organisms.
(17)
17- The property of the vaporization of water at temperatures less than boilingpoints is very important to us.
(18)
18- The rise of water in capillary tubes is very important for plants and trees.
(19)
Choose the correct answer
Close water molecules are attracted to each other by relatively low electricattraction called ........... bond.
Hydrogen
Ionic
Covalent
Peptide
(20)
2- The amount of heat required to increase the temp. of one gram of matter 1Celsius degree is called ...........
Latent heat
Specific heat
Heat amount
Work
(21)
Plants lose water by .......... process to decrease their temperature.
Sweating
Respiration
Execration
Transpiration
(22)
- Animals lose water to decrease their temperatures in the form of.......
Lymph
Sweat
Blood
Juices
(23)
When the temp. of water becomes less than 4C, ..............
it expands
it shrinks
it doesn't change
its density increases
(24)
When substances dissolve in water,.........
its freezing point decreases
its freezing point increases
its boiling point decreases
Neither boiling point nor freezing point changes
(25)
Write the scientific term
A molecule which has a negative pole (atoms with molecular negative charges)and positive pole (atoms with positive charges).
(26)
- A bond between molecules containing hydrogen atoms by which negativehydrogen atoms of a molecule attract the positive oxygen atoms of another one
(27)
The amount of heat required to increase the temp. of one gram of matter Celsius degree
(28)
The cohesion of the molecules on the surface of a fluid to occupy the leastpossible volume
