LEARNING MATERIAL
ST JOSEPH COLLEGE OF TEACHER EDUCATION FOR WOMEN, ERNAKULAM
PRACTICAL 107.1 FOR EDU 103 CREATION OF BLOG AND UPLOADING ANY LEARNING MATERIAL IN THE BLOG
Submitted to Submitted by
Mrs. ANU CLEETUS ASWATHY AJI P
ASSISTANT PROFESSOR PHYSICAL SCIENCE
ST JOSEPH COLLEGE OF TEACHER ROLL NO: -8
EDUCATION FOR WOMEN 2022-24
ERNAKULAM
Hi friends,
Today we are going to learn about water. We know that water is a precious naural science. Water is essential for sustaning life n earth. We use water for various purpose in ur daly life. In this materal we move through the components and the characteristic prperties of water. Look through the given frames and read the following paragraph carefully. Try to answer the question. It‘s really a funny activity.
Good luck
FRAME 1 water
Water is the cause for the origin of life on earth. It is interesting that 65 % of the body parts of animals and plants contain water. Water is essential not only for sustaining life but also for agriculture, industry, energy production and transportation. We use water for different purposes in day-to-day life. We get water in large amount from different natural resources. Rainwater, wells, backwaters, streams, rivers abd iceans are different water resources.
Which of the following is not a source of freshwater?
?
Sorry!
Your nswer is wrong. Rainwater is considered the purest form of water and is an important source of freshwater.
Frame 1
a) Rainwater
Sorry!
Your answer is wrong. Wells are the source of freshwater.
Frame 1
c) Wells
Sorry!
Your answer is wrong. Rivers are the sources of freshwater.
Frame 1
d) Rivers
Your answer is correct. Oceans are the sources of saline water.
Next
b) Oceans
FRAME 2 components of water
Water is formed by the combination of the constituent elements, hydrogen and oxygen. Hydrogen and oxygen can be produced by decomposing water. Water can be decomposed into its components by electrolysis. Water molecule contain hydrogen and oxygen atom in the ra tio 2:1. Hence it is represented as H2O.
What is the chemical formula of water?
?
Sorry!
Your answer is wrong. HCl is the chemical formula of hydrogen chloride.
Frame 2
c) HCl
Sorry!
Your answer is wrong. CO2 is the chemical formula of carbon dioxide.
Frame 2
d) CO2
Your answer is correct. The chemical formula of water is H2O.
Next
a) H2O
Sorry!
Your answer is wrong. CO is the chemical formula of Carbon monoxide.
Frame 2
b) CO
FRAME 3 Boiling point
Water is a substance found in nature in all the three states of matter namely solid, liquid and gas. Water exist in the liquid state at a temperature between 0°C and 100° C. But water changes to vapour at any temperature upto 100°C. The temperature at which water boils at normal atmospheric pressureis its boiling point. The boiling point of water is 100°C. Once water starts boiling, the temperature will not change because all the heat supplied is utilized for the change of state.
What is the boiling point of water?
?
Your answer is correct. The boiling point of water is 100°C
Next
c) 100°C
Sorry!
Your answer is wrong. 37°C is the average normal body temperature
Frame 3
d) 37°C
Sorry!
Your answer is wrong. 120°C is the temperature at which water boils in a pressure cooker.
Frame 3
b) 120°C
Sorry!
Your answer is wrong. 0°C is the freezing point of water
Frame 3
a) 0°C
FRAME 4 Freezing point
Water changes to ice when its temperature reaches 0°C. The temperature at which water freezes to solid at normal atmospheric pressure is its freezing point. The freezing point of water is 0°C. Normally, all substances shrin on cooling and their volume decreases. This increase its density. When water is cooled, its density increases and the cold water goes down. This occur till the temperature reaches 4°C Water below 4°C converted to ice, its volume increases and the density decreases.
What is the freezing point of water?
?
Your answer is correct. The freezing point of water is 0°C.
Next
c) 0° C
Sorry!
Your answer is wrong. 4°C is the temperature at which liquid water has the highest density.
Frame 4
a) 4°C
Sorry!
Your answer is Wrong. -2°C is the freezing point of sea water.
Frame 4
d) -2°C
Sorry!
Your answer is wrong. -38.83°C is the freezing point of mercury.
Frame 4
b) -38.83°C
FRAME 5 surface tension
The molecules of a liquid attract each other. The number of molecues in vapour form just above the surface of water is less than those on the surface. Hence the attraction towards the sides and the interior will be greater. Consequently the liquid surface behaves like a stretched membrane. This behaviour causes surface tension. Surface tension act in such a way so as to reduce the surface area of a liquid. For the definite mass of a substance, surface area is minimum for spherical shape.That is why liquid droplets assume spherical shape.
Why liquid droplets assume spherical shape?
?
Sorry!
Due to high heat capacity, water can hold more heat than other substances.
Frame 5
a) Heat capacity
Your answer is correct. Liquid droplets assume spherical shape due to surface tension.
Next
d) Surface tension
Sorry!
Your answer is wrong. Freezing point of water is the temperature at which liquid water freezes to ice at normal atmospheric pressure.
Frame 5
b) Freezing point
Sorry!
Your answer is wrong. Boiling point of water is the temperature at which water boils at normal atmospheric pressure.
Frame 5
c) Boiling point
FRAME 6 Heat capacity
Two third of the earth is water. So the water plays a crucial role in regulating temperature of the earth. This is due to high heat capacity of water. High heat capacity is one of the properties of water that make essential to life. Water has the ability to hold more heat when compared to other substance. Therefore water is used in radiation to regulate the heat in automobile. It is used to cool hot objects.
Which property of water plays a major role in regulating temperature on the earth?
?
Sorry!
Your answer is wrong. Water can dissolve various substances and is used for preparing solutions.
Frame 6
d) Universal solvent
Sorry!
Water changes to ice when its temperature reaches 0°C
Frame 6
c) Freezing point
Sorry!
Your answer is wrong. Surface tension reduces the surface area of the liquid.
Frame 6
b) Surface tension
Water has high heat capacity when compared to other substance.
Next
a) Heat capacity
FRAME 7 classification
Rainwater gets filtered and flows through the soil to reach well, rivers and sea. During this process many substances present in the soil get dissolved in it. It has been found that mostly the salts of calcium and magnesium get dissolved in water. The hardness of water is due to the presence of dissolved salts of calcium and magnesium. If water consist of higher concentration of minerals such as magnesium and calcium it is classified as hard water and if the water consist of lower concentration of minerals it is classified as soft water. The water in which soap gives lather easily is called soft water. The water in which soap does not form lather easily is called hard water.
Which water gives lather readily with soap?
?
Sorry!
Your answer is wrong. Hard water does not give lather with soap
Frame 7
b) Hard water
Correct answer. Soft water gives lather with soap.
Next
a) Soft water
Sorry!
Sea water is considered to be hard. It dies not give lather with Soap.
Frame 7
d) Sea water
Sorry!
Heavy water is water molecules containing deuterium, the isotope of hydrogen.
Frame 7
c) Heavy water
FRAME 8
The hardness of water can be classified as temporary hardness and permanent hardness. The hardness of water containing bicarbonates of calcium and magnesium is removed during boiling. This type of hardness of water is known as temporary hardness. The hardness of water containing the chlorides and sulphates of calcium and magnesium isnot removed even after boiling. This is permanent hardness. Permanent hardness of water can be remived only by using certain chemicals.
Which salt causes the temporary hardness of water?
?
Sorry!
Your answer is wrong. Chlorides of Ca & Mg
Cause permanent hardness of water.
Frame 8
b) Chlorides of Ca & Mg
Sorry!
Your answer is wrong. Sulphates of Ca & Mg causes permanent hardness of water.
Frame 8
c) Sulphates of Ca & Mg
your answer is correct. Temporary hardness is due to bicarbonates of Ca & Mg in water.
a) Bicarbonates of Ca &Mg
Sorry!
Your answer is wrong. Nitrates of Ca & Mg cause permanent hardeness of water.
Frame 8
d) Nitrates of Ca & Mg