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Environmental Chemistry Complete Notes..

Environmental Chemistry Environmental chemistry: It is the branch of chemistry that deals with the study of various chemical processes taking place in the various segments of the environment. Broadly speaking, it is the study of the sources, transportation, reactions, effects and the ultimate of the chemical species occurring in one or more segments of the environment. Components of Environment : Atmosphere:   This comprises a blanket of gaseous layer around earth. Hydrosphere :  This comprises about 96% of earth’s surface & includes all   sources of water like oceans rivers lakes, glaciers, ground water etc. Lithosphere :  It refers to earth’s solid crust containing the outer mineral cover. It comprises soil, minerals, organic matter etc.  Biosphere:   It refers to the domain of living organism in covalent with atmosphere hydrosphere as well as lithosphere.    Environmental pollution...
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States of Matter Test Questions set 01



CHEMISTRY- XIth

(STATES OF MATTER)

Full Marks 35                                                                                                         Time: 1:30 hr                       
MULTIPLE CHOICE QUESTIONS:                                                                          1X5=5

1. Under which of the following conditions does a real gas deviate the most from the ideal gas equation?
(a) High temperature and low pressure (b) Low temperature and high pressure                (c) High temperature and low pressure              (d) Low temperature and low pressure

2. According to Charles's law, the volume of a fixed mass of gas at a constant pressure is proportional to its temperature on
(a) the Celsius scale        (b) the Fahrenheit scale                                (c) the kelvin scale           (d) all temperature scales

3. At STP,0.5 mol of H2 gas and 1.0 mol of He gas have equal
(a) average kinetic energies        (b) molecular speeds     (c) volumes        (d) effusion rates
4. The KInetic energy of one mole of an ideal gas is proportional to
(a) T       (b) P      (c) 1/T   (d) 1/P

5. The absolute Zero is defined as the temperature at which:
(a) all molecular motion ceases (b) liquid helium boils     (c) ether boils    (d) all of the above

VERY SHORT ANSWER TYPE QUESTIONS:                                                            1X5=5

6. What is Dalton's law of partial pressure ?

7. What is the compressibility factor ?

8. What is critical temperature ?

9. Why are liquid Drops spherical ?

10. What is laminar flow ?

SHORT  ANSWER TYPE QUESTIONS:                                                                   2X5=10

11. What is the partial pressure of a gas?

12. At 0⁰C, the density of a certain gaseous oxide at 2 bar is the same as that of dinitrogen at 5 bar. What is the molecular mass of the oxide ?

13. What factors determine the rate of evaporation of a liquid ?

14.  The drain cleaner, Drainex , contains small bits of aluminium, which react with caustic soda to produce dihydrogen. What volume of dihydrogen will be released at 20⁰C and 1 bar when 0.15 of a aluminium reacts with caustic soda ?

15. Which is more viscous, acetone or water ? Explain why.

LONG ANSWER TYPE QUESTIONS:                                                                  3X5=15

16. What are the postulates of the kinetic theory of gases ?

17. A student forgot to pour the reaction mixture into a round-bottomed flask at 27⁰C and placed the flask on a flame. A while later, he/she used a pyrometer to find the temperature of the flask. If the temperature was 477⁰C, what fraction of air had been expelled ?

18. The pressure of 1g of an ideal gas A at 27⁰C is 2 bar. When 2g of another ideal gas B is introduced into the same flask at the same temperature, the pressure becomes 3 bar. Find a relationship between the molecular masses of A and B.

19. How do real gases deviate from the ideal behaviour ?

20. Calculate the total pressure of a mixture of 8g of dioxegen and 4g of dihydrogen confined in a vessel of 1 dm3 at 27⁰C. (R = 0.083 bar dm3 k-1 mol-1)

BY:Anjani Kumar Singh.


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