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प्रश्न
The best evidence for the existence and movement of particles in liquids was provided by :
विकल्प
John Dalton
Ernest Rutherford
J.J. Thomson
Robert Brown
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उत्तर
Robert Brown
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संबंधित प्रश्न
Define the following term of Matter .
Name two processes which provide the best evidence for the motion of particles in matter.
When a crystal of potassium permanganate is placed at the bottom of water in a beaker, the water in the whole beaker turns purple on its own, even without stirring. This is an example of :
Name one element, one compound and one mixture.
State two physical properties on the basis of which metals can be distinguished from non-metals.
There are three substances X, Y and Z. The substance X does not have a fixed melting point or boiling point and it still shows the individual properties of its constituents. The substance Y is a pure substance which occurs in nature as such. The substance Y has a fixed melting point and boiling point but it cannot be broken down into simpler substances by any chemical means. The substance Z is also a pure substance whose properties are entirely different from those of its constituents. The substance Z can, however, be divided by electrolysis into two substances which belong to the same class of substances as Y.
- What type of substance could X be ? Name one substance like X.
- What type of substance could Y be ? Name one substance like Y.
- What type of substance could Z be ? Name one substance like Z.
- Which process involves absorption or release of an appreciable amount of energy : formation of substance X or formation of substance Z ?
- Name the three groups into which all the substances like Y are divided on the basis of their properties.
Out of a colloid, solution and a suspension :
which one has the smallest particles ?
What difference in the property of two miscible liquids enables their separation by fractional distillation ?
What is the general name of the process by which tea-leaves are separated from prepared tea ?
Name the process which can be used to purify an impure sample of copper sulphate.
Describe a method for separating a mixture of iron filings and sulphur powder other than that by using a magnet.
Explain how, impure copper sulphate can be purified by crystallisation.
Draw a labelled diagram of the fractional distillation apparatus used for separating a mixture of alcohol and water.
The technique which is used to separate particles of a solid suspended in a liquid quickly is called :
The given mixture contains three constituents A, B and C. The constituent A is a yellow coloured, solid element which dissolves in a liquid D. The constituent B is a blue coloured salt which is insoluble in liquid D but dissolves easily in another liquid E. The constitudent C is a liquid which is used in cooking food and forms a solid fat on hydrogenation.
(a) What do you think could (i) constituent A, and (ii) liquid D be ?
(b) What could (i) constituent B, and (ii) liquid E be ?
(c) What could liquid C be ?
(d) How will you separate the mixture containing A, B and C ?
Wipe the board with a duster and then tap the duster against the table. What do you see?
Diffentiate between absorption and adsorption.
What type of matter glass is?
The non S I and S I units of some physical quantities are given in column A and column B respectively. Match the units belonging to the same physical quantity:
| (A) | (B) | ||
| (a) | degree celsius | (i) | kilogram |
| (b) | centimetre | (ii) | pascal |
| (c) | gram per centimetre cube | (iii) | metre |
| (d) | bar | (iv) | kelvin |
| (e) | milligram | (v) | kilogram per metre cube |
Atoms or groups of atoms having a charge are called ______.
