256. Temporary hardness of water is due to the presence of

1. 1. Magnesium bicarbonate

   
   
   

   2. Calcium carbonate

   
   
   

   3. Calcium chloride

   
   
   

   4. Magnesium sulphate

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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257. The molarity of pure water at 4^°C is

1. 1. 2.5 M

   
   
   

   2. 5 M

   
   
   

   3. 1 M

   
   
   

   4. 55.5 M

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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258. Which one is the weakest acid ?

1. 1. HF

   
   
   

   2. HCI

   
   
   

   3. HBr

   
   
   

   4. HI

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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259. The oxyacid of halogen has maximum acidic nature

1. 1. HCIO

   
   
   

   2. HCIO₂

   
   
   

   3. HCIO₃

   
   
   

   4. HCIO₄

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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260. Bromine gas turns starch iodine paper

1. 1. Blue

   
   
   

   2. Red

   
   
   

   3. Colourless

   
   
   

   4. Yellow

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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