OBJECTIVE TYPE QUESTIONS:
Fill in the blanks:
________________ is the purest form of water.
Symbols are used for representing the ___________.
In filtration, the solid substance left behind on the filter paper is called________.
The symbol for sodium is__________.
The percentage of fresh water on earth is___________.
State True or False.
1. Oil spills do not harm marine life.
2. Increasing population is the leading cause of decreasing water table.
3. The symbol for potassium is P.
4. Saline water is fit for drinking.
5. A symbol is an abbreviation which represents one molecule of an element.
Match the following
Column A
Column B
Rain
Filtration
Sea water
Purest form of water.
A source of fresh water
Loading
Residue
River
Alum
Salty
SUBJECTIVE TYPE QUESTIONS
Define: Water table, Chemical formula, Filtration.
Give reason for the following :
Water is essential for plant.
Water is known as the universal solvent.
Differentiate between: (i) Melting and Freezing (ii) Condensation and Boiling
(iii) Metal and Non-metal.
G. Answer the following question in details.
1. What are the effects of water pollution?
2. What are the main causes of water pollution?
Answers
Answer:
Fill in the blanks
Rainwater is the purest form of water.
Symbols are used for representing the idea, object or relationship.
In filtration, the solid substance left behind on the filter paper is called residue.
The symbol for sodium is Na.
The percentage of fresh water on earth is 3%. .
True or false
1. Oil spills do not harm marine life. (True)
2. Increasing population is the leading cause of decreasing water table. (True)
3. The symbol for potassium is P. (False)
4. Saline water is fit for drinking. (False)
5. A symbol is an abbreviation which represents one molecule of an element. (True)
Match the column
Rain----------------------------------purest form of water
Rain----------------------------------purest form of waterSea water------------------------- salty
saltyA source of fresh water------ River
Residue ---------------------------- Filtration
Alum-------------------------------- Loading
Define:
Water Table-- The water table is an underground boundary between the soil surface and the area where groundwater saturates spaces between sediments and cracks in rock.
Chemical formula-- A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus (+) and minus (−) signs.
Filtration-- Filtration is a process used to separate solids from liquids or gases using a filter medium that allows the fluid to pass through but not the solid.
Give reasons:
Water is essential for plants
Water is used for transpiration carrier of nutrients from the soil to green plant tissues. Water forms over 90% of the plant body by green or fresh weight basis. Plants can synthesis food through photosynthesis only in the presence of water in their system. Water helps to maintain the turgidity of cell walls.
Water is called as the universal solvent
Water is called the "universal solvent" because it is capable of dissolving more substances than any other liquid. ... This allows the water molecule to become attracted to many other different types of molecules.
Differentiate between:
(i) Freezing and melting- Freezing is the change that occurs when a liquid changes into a solid as the temperature decreases. Melting is the opposite change, from a solid to a liquid as the temperature increases.
ii) Condensation and boiling- If the fluid is being transformed from liquid to vapor through heat addition, then the process is referred to as boiling or evaporation. If vapor is being transformed to liquid by heat removal, then the process is referred to as condensation.
iii) In the attachment above....
Answers in detail
1. What are the effects of water pollution?
Diseases: In humans, drinking or consuming polluted water in any way has many disastrous effects on our health. It causes typhoid, cholera, hepatitis and various other diseases. Destruction of Ecosystems: Ecosystems are extremely dynamic and respond to even small changes in the environment.
2. What are the main causes of water pollution?
Discharge of domestic and industrial effluent wastes, leakage from water tanks, marine dumping, radioactive waste and atmospheric deposition are major causes of water pollution. Heavy metals that disposed off and industrial waste can accumulate in lakes and river, proving harmful to humans and animals.
hope it helps you........
