21. Photoconductors of xerox machine

1. 1. Black phosphorus

   
   
   

   2. Tellurium

   
   
   

   3. Mercury

   
   
   

   4. Selenium

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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22. The ease of liquefication of noble gas decreases in the order

1. 1. Xe > Kr > Ar > Ne > He

   
   
   

   2. He > Ne > Ar > Kr > Xe

   
   
   

   3. Ar > Kr > Xe > He > Ne

   
   
   

   4. Kr > Xe > He > Ar = Ne

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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23. A colourless gas with smell of rotten egg is

1. 1. SO₂

   
   
   

   2. SO₃

   
   
   

   3. H₂S

   
   
   

   4. None

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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24. The first ever compound of noble gas was prepared by

1. 1. Ramsay

   
   
   

   2. Bartlett

   
   
   

   3. Berzelius

   
   
   

   4. Cavendish

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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25. SO₂ + CI ₂^sunlight→Product. The product is

1. 1. Chloroform

   
   
   

   2. Sulphuryl chloride

   
   
   

   3. Sulphuric acid

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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