Group-1-roll no-1 to 7
What is the main source of water on earth?
Rain
Rock : ______ :: Boat : Float
Sink
Sand and gravel may be separated from each other through using______________ .
A sieve
All the animals, including human beings, need _______ to live.
Oxygen
__________ is required for burning.
Oxygen
Define Soluble and insoluble substance.
Insoluble-An insoluble substance is a substance (solid) that will not dissolve in a solvent even after mixing (eg; sand and water).
Soluble-soluble is something that can be dissolved.
The --------------- is the lowest layer of our atmosphere.
The troposphere is the lowest layer of our atmosphere.
Name any two sources of surface water.
Lake, River, pond
How will you prove that air has mass?
We can take two balloon (one filled with air another one without air)and tie it with a long scale. we will observe that the one which has air filled in it tilt and hence proved that air has mass.
What are the two important properties of air?
1. It occupies space.
2. It has mass.
Define biosphere.
the regions of the surface, atmosphere, and hydrosphere of the earth occupied by living organisms.
How to make tap water fit for drinking?
Boiling or Filtering
What are the three classification of sources of water?
Rain water, Underground water, Surface water
What is the composition of air?
Nitrogen-79%
Oxygen-21%
Carbon dioxide-0.03
Name any three sources of underground water.
Well, Handpump, Spring water
What are the four uses of water?
1. Domestic
2.Industries
3.Hydroelectricity
4.Plantation
5.Medical Science
What is impurity?
Impurities are substances that are present in small quantities in another substance and make it dirty or of an unacceptable quality.
What is Filtrate?
The clear liquid which passed through the filter is called filtrate.
Define Sediment .
The impure particle settle down and form a layer is called sediment.
What is ozone layer?
The ozone layer is a thin part of the Earth's atmosphere that absorbs almost all of the sun's harmful ultraviolet light
What are the five properties of water.
1. It is colourless
2. It has no taste.
3. It is odourless.
4. It is universal solvent.
5.It is transparent.
Define filtration
The process of impure water passing through a filter is called filtration.
What is chlorination.
CHLORINATION- The addition of chlorine to water helps in killing germs that are not visible to the naked eyes. This process of purification is known as chlorination.
Explain Distillation.
Distillation is a process where a mixture made of two or more liquids (called "components") with different boiling points can be separated from each other.
Define Decantation .
Decantation is pouring out of upper clear layer of liquid into another container to separate two liquids.