21. The M.K.S system was first introduced by

1. 1. Archimedes

   
   
   

   2. Eienstein

   
   
   

   3. Newton

   
   
   

   4. Giorgi

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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22. Which one of the following laws directly explains the law of conservation of mass ?

1. 1. Hund's law

   
   
   

   2. Dalton's law

   
   
   

   3. Avogadro's law

   
   
   

   4. Berzelius hypothesis

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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23. Which one of the following mixture is homogeneous ?

1. 1. Starch and sugar

   
   
   

   2. Methanol and water

   
   
   

   3. Graphite and charcoal

   
   
   

   4. Calcium carbonate and calcium bicarbonate

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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24. A gas is found to have the formula (CO)_n. Its vapor density is 70. The value of n must be

1. 1. 5

   
   
   

   2. 4

   
   
   

   3. 9

   
   
   

   4. 6

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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25. In known elements, the maximum number is of

1. 1. metals

   
   
   

   2. non-metals

   
   
   

   3. metalloids

   
   
   

   4. none of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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