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प्रश्न
What's the solution?
We need to rub salt on a corncob, but only salt crystals are available.
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उत्तर
We can pound salt crystals. Either we can use mortar pestle or we can also crush the crystals of salt in a grinder. Such powdered salt can be easily applied on the corncob.
संबंधित प्रश्न
The smallest unit of matter that exists freely in nature is called ...........
Select the correct alternative
The molecules can move freely anywhere in
- gases
- liquids
- solids
- none of the above
Which of the following is not an emulsion ?
Tincture of iodine has antiseptic properties. This solution is made by dissolving :
When the solid A is added to water, it dissolves with the evolution of a lot of heat and making little explosions to form two products B and C. The properties of products B and C are entirely different from those of solid A as well as water. Moreover, products B and C cannot be reconverted into solid A and water. When another solid D is added to water, it dissolves with the absorption of a little heat to form a product E which cools down. The product E shows the properties of both, solid D as well as water. Moreover, product E can be converted into solid D and water.
(a) What type of change occurs when solid A is dissolved in water ? Why ?
(b) What type of change occurs when solid D is dissolved in water ? Why ?
(c) Name a metal which you think could behave like solid A. Also name the products B and C.
(d) Name the solid D if it is the one which is used in making ordinary dry cells.
(e) Name the process by which D can be recovered from E.
Explain the meaning of the term ‘matter’.
Asmita went to buy an earthen pot. There she saw many things kept for sale.
How did she identify what she needed?
Why wires cannot be drawn from materials such as stone or wood?
Non-metals are usually poor conductors of heat and electricity. They are non-lustrous, non-sonorous, non-malleable and are coloured.
Name a non-metal which exists as a liquid at room temperature.
Gases do not diffuse very easily.
