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Give reasons (a) A gas fills completel...

Give reasons
(a) A gas fills completely the vessel in which it is kept.
(b) A gas exerts pressure on the walls of the container.
(c) A wooden table should be called a solid.
(d) We can easily move our hand in air but to do the same through a solid block of wood. we need a karate expert.

Text Solution

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The force of attraction between particles of gas is negligible Because of this, particles of gas move in all directions. Thus, a gas fills the vessel completely in which it is kept.
Particles of gas move randomly in all directions at high speed. As a result, the particles hit each other and also hit the walls of the container with a force. Therefore, gas exerts pressure on the walls of the container
A wooden table has fixed shape and fixed volume, which are the main characteristics of solid. Thus a wooden table should be called a solid.
Particles of the air have large spaces between them. On the other hand, wood has little space between its particles. Also, it is rigid. For this reason, we can easily move our hands in the air, but to do the same through a solid block of wood, we need a karate expert.
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A solution which remains in equilibrium with undissolved solute , in contact , is said to be saturated . The concentration of a saturated solution at a given temperature is a called solubility . The product of concentration of ions in a saturated solution of an electrolyte at a given temperature is called solubility product (K_(sp)) . For the electrolyte A_(x),B_(y) with solubility S. The solubility product (K_(sp)) is given as K_(sp) = x^(x) xx y^(y) xx S^(x-y) . While calculating the solubility of a sparingly . soluable salt in the presence of some strong electrolyte containing a common ion , the common ion concentration is practically equal to that of strong electrolyte containing a common ion . the common ion soncentration is practically equal to that of strong electrolyte . If in a solution , the ionic product of an electroylte exceeds its K_(sp) value at a particular temperature , then precipitation occurs . If two or more electrolyte are presentt in the solution , then by the addition of some suitable reagent , precipitation generally occurs in increasing order of their k_(sp) values . Solubility of some sparingly soluable salts , is sometimes enhanced through complexation . While we are calculating the solubility of some sparingly or pH of an electrolyte , the nature of cation of anion should be checked carefully whether there ion (s) are capable of undergoing hydrolysis or not . If either or both of the ions are capable of undergoing hydrolysis , it should be taken into account in calculating the solubility . While calculating the pH of an amphiprotic species , it should be checked whether or not cation can undergo hydrolysis . Total a_(H^(-)) = sqrt(K_(a_(1)xxK_(a_(2)))) (if cation do not undergo hydrolysis ) a_(H^(+)) = sqrt(K_(a_(1))((K_(w))/(K_(b)) - K_(a_(2)))) (if cation also undergoes hydrolysis ) where symbols have usual meaning . Solubility of solids into liquids is a function of temperature alone but solubility of gases into liquids is a function of temperature as well as pressure . The effect of pressure on solubility of gases into liquids is governed by Henry's law . The solubility of PbSO_(4) in water is 0.0303 g/l at 25^(@)C , its solubility product at that temperature is

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NCERT ENGLISH-MATTER IN OUR SURROUNDINGS-Exercise
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  2. (a) Tabulate the differences in the characteristics of states of matte...

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  3. Give reasons (a) A gas fills completely the vessel in which it is ke...

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  4. Liquids generally have lower density as compared to solids but you mus...

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  5. Convert the following temperatures to the celsius scale. (a) 300k (...

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  6. What is the physical state of water at: a. 250^(@)C b. 100^(@)C?

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  7. For any substance, why does the temperature remains constant during th...

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  8. Suggest a method to liquefy atmospheric gases.

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  9. Why does a desert cooler cool better on a hot dry day?

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  10. How does the water kept in an earthen pot (mataka) become cool during ...

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  11. Why does our palm feel cold when we put some acetone or petrol or per...

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  12. Why are we able to sip hot tea or milk faster from a saucer rather tha...

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  13. What type of clothes should we wear in summer?

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  14. Convert the following temperatures to the celsius scale. (a) 293k (...

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  15. Convert the folowing temperature to the kelvin scale. (a) 25^(@)C (b...

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  16. Give reason for the following observations. (a) Naphthalene balls d...

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  17. Arrange the following substances in increasing order of forces of attr...

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  18. What is the physical state of water at- (a) 25^(@) (b) 0^(@)C (c) 1...

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  19. Give two reasons to justify- (a) Water at room temperaure is a liqui...

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  20. Why is ice at 273k more effective in cooling than water at the same te...

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