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please someone answer the questions now

1.copper sulphate crystals lose their blue colour and turn white when heated strongly,why?

2.you are provided with 2 test tubes.one of them contains water and the other contains acid solution.how will you find out which of the test tubes contain water without tasting the solutions?

3.how will you collect hydrogen gas?

4.a student drpped a few pieces of marble in dil.HCl contained in a test tube.The evolved gas was passed through lime water.what change would be observed in lime water?write a balanced chemical equations for both th changes observed.

5.how can you find the strength of a given acidic or a basic solution?

6.write two oservations you would make when quick lime is added to water.

7.what reaction is evovled in the setting of plaster of paris into hard mass?

1. This is because copper sulphate is pentahydrate and the crystals lose their water of crystallisation.

2. For this, you can dip a blue litmus paper in each test tube. The solution which turns blue litmus red, will be the acid.

3. You can collect hydrogen gas by performing a reaction which evolves H2 gas. Hydrogen gases can simply be collected by the downward displacement of water. 

4. Marble(CaCO3) reacts with HCl to form calcium chloride and CO2 and H2O gas.

    CaCO3 + 2HCl -----> CaCl2 + H2O + CO2

     This CO2 gas reacts with lime water [Ca(OH)2] to form white ppt. of CaCO3 and water

       Ca(OH)2 + CO2 -----> CaCO3 + H2O

5. We can find the strength of given acid or base by finding it's pH. i.e. amount of H+ ions released by the acid/base when dissolved in water.

6. observations when CaO is added to water - i) CaO reacts with water to form Ca(OH)2 i.e. slaked lime it is a combination reaction (ii) It is a highly exothermic reaction, which causes the evolution of heat and bubbles. (iii) the solid calcium oxide puffs up. 

7. Combination reaction

CaSO4. 1/2H2O + 1 1/2H2O -----> CaSO4. 2H2O

(CaSO4. 1/2H2O = Plaster of paris, CaSO4. 2H2O = gypsum)

hope this helps!! 

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Man, you asked a lot many questions!! :P

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1)copper sulphate crystals are blue due to the presence of water called water of crystalisation.When heated the crystals lose water and they turn to a white colour powder.

2)Heat both the testubes properly.The water will surely turn to vapour at 100 degree celcius.With the help of thermometer find the boiling point.The liquid that turns to vapour at 100 degree celcius is water.

3)hydrogen gas evolved after a reaction can be obtained with the help of a delivery tube connected to anothe testube.Hydrogen will pass through the delivery tube and get collected in the testube.

4)CaCO3 + 2HCl ------> CaCl2+ H2O +CO2

When CO2 is passed through lime water it will turn milky due to formation of a white coloured powder called Calcium Carbonate.

Ca(OH)2 + CO2 -------> CaCO3 + H2O

5) The strength can be found by using a universal indicator called pH.It is a scale used to find the nature of solution.The lesser the pH value the more acidic the sample is and the more the pH value the more basic the sample is.

6) a) The water will start boiling without heating it as the reaction is highly exothermic.

  b) The reaction is very vigorous.

7) CaSO4 . 1/2 H2O + 1 1/2 H2O -----> CaSO4 . 2 H2O

hope this helps u

srry if iam wrong

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