176. Dry powder extinguishers contains

1. 1. Sand

   
   
   

   2. San + baking soda

   
   
   

   3. Sand + Na₂CO₃

   
   
   

   4. Sand + K₂CO₃

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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177. Which of the following oxide is neutral ?

1. 1. CO

   
   
   

   2. SiO₂

   
   
   

   3. ZnO

   
   
   

   4. P₂O₅

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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178. Percentage of lead in lead pencil is

1. 1. Zero

   
   
   

   2. 20

   
   
   

   3. 40

   
   
   

   4. 80

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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179. Which is the catalyst used in manufacture of sulphuric acid by contact process ?

1. 1. Fe

   
   
   

   2. NO

   
   
   

   3. N₂O

   
   
   

   4. V₂O₅

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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180. Which is the catalyst used in manufacture of sulphuric acid by lead chamber process ?

1. 1. Fe

   
   
   

   2. Ni

   
   
   

   3. Pb

   
   
   

   4. Oxides of nitrogen

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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