16. The α particles are

1. 1. high energy electrons

   
   
   

   2. positively charged hydrogen ions

   
   
   

   3. high energy X-ray radiations

   
   
   

   4. double positively charged helium nuclei

   
   
   

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   NA

   Correct Option: D

   NA

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17. Which one radiation has the highest energy ?

1. 1. α-particle

   
   
   

   2. β-particles

   
   
   

   3. γ-rays

   
   
   

   4. None of these

   
   
   

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   NA

   Correct Option: C

   NA

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18. Which one of the following is not radioactive ?

1. 1. Astanine

   
   
   

   2. Francium

   
   
   

   3. Tritium

   
   
   

   4. Zirconium

   
   
   

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   NA

   Correct Option: D

   NA

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19. 1 Curie of activity is equivalent to

1. 1. 3.7 x 10¹⁷ disintegration per second

   
   
   

   2. 3.7 x 10¹⁰ disintegration per second

   
   
   

   3. 3.7 x 10¹⁴ disintegration per second

   
   
   

   4. 3.7 x 10³ disintegration per second

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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20. The activity of radioisotope change with

1. 1. temperature

   
   
   

   2. pressure

   
   
   

   3. chemical environment

   
   
   

   4. emmission of radiation

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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