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प्रश्न
A notebook has lustre while an eraser does not.
विकल्प
True
False
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उत्तर
This statement is False.
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संबंधित प्रश्न
Short Answer Type Question:
What is the reason for grouping materials?
Sand paper is a good example for smooth materials.
Oil mixes with water.
Paheli prepared a blue coloured solution of copper sulphate in beaker A and placed an iron nail in it. Boojho prepared a yellowish green solution of ferrous sulphate in beaker B and placed a copper wire in it. What changes will they observe in the two beakers after an hour?
Match the substances in Column A with their applications given in Column B.
|
Column A |
Column B |
| (a) oxygen | (i) for making crackers |
| (b) copper | (ii) for disinfecting water |
| (c) sulphur | (iii) all living beings inhale during breathing |
| (d) iron | (iv) for making electric wires |
| (e) chlorine | (v) for making rails |
Some of the following statements are incorrect. Find the incorrect statements and correct them.
- The property of metals by virtue of which they can be drawn into wires is called ductility.
- Metals are good conductors of electricity but poor conductor of heat.
- Articles made up of metals produce ringing sound when struck hard.
- Oxides of non-metals and metals are acidic in nature.
- A less reactive metal displaces a more reactive metal from its salt solution in water.
Complete the crossword given in the figure with the help of the clues.
Across
1. Which is generally hard, ductile, malleable and sonorous.
2. A metal is called so it can be drawn into wires.
3. Metal bells are used because of this property.
Down
4. A metal generally used for making jewellery.
5. A metal which is liquid at room temperature.
6. A metal which reacts with acid as well as base to form hydrogen gas.
7. Substances used to enhance the growth of plants.
8. Property by virtue of which metals can be beaten into thin sheets.
Which of the following materials is not lustrous?
Why do you think oxygen dissolved in water is important for the survival of aquatic animals and plants?
Sugar, salt, mustard oil, sand, sawdust, honey, chalk powder, petals of flower, soil, copper sulphate crystals, glucose, wheat flour are some substances given to Paheli. She wants to know whether these substances are soluble in water or not. Help her in identifying soluble and insoluble substances in water.
