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प्रश्न
Define: Compounds
उत्तर
Compounds are pure substances composed of two or more elements in definite proportion by mass and has properties, entirely different from those of its constituents elements.
Compound, are made up of different types of atoms combined chemically.
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संबंधित प्रश्न
Match the columns.
| column A | column B |
|
1. to separate grain from chaff |
a. filtration |
| 2. to saparate sawdust from water | b. sedimentation and deeantation |
| 3. to separate iodine from sodium chloride | c. winnowing |
| 4. to separate iron fillings from sand | d.sublimation |
|
5. it is used to separate sand and water |
e maganetic separation |
|
|
f .handpicking |
Give the symbols of: Carbon, calcium, copper, chlorine, cobalt, argon.
Define: Formula
What is meant by 2H and H2
The important physical properties of substances are colour, odour, nature, density & solubility in water.
Name - a poisonous gas almost as heavy as air.
Elements are classified into – Metals – Non-metals – Metalloids – Noble gases. State which of A, B, C, D is a –
1. Metallic element
2. Non-metallic element
3. Metalloid
4. Noble gas.
A: Is non-malleable, non-ductile & a poor conductor of electricity ___________
B: Has lustre, is malleable and ductile & a good conductor of heat ___________
C: Is unreactive and inert and present in traces in the air _________
D: Shows properties of both metals and non-metals ___________
Give the name of the radical - NO3
Write the names of elements from the following symbol:
Pt
Select the correct answer from A, B, C, D & E for the statement given below :
A non-metal that is lustrous.
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Reason: Only nitrogen, oxygen and neon gases exist in air.
