In an experiment to determine the molar heat of reaction when zinc displaces copper, 0.4g of zinc powder were added to 25.0cm³ of 2.0M copper...

      

In an experiment to determine the molar heat of reaction when zinc displaces copper, 0.4g of zinc powder were added to 25.0cm³ of 2.0M copper (II) sulphate solution. The temperature of copper (II) sulphate solution was 24ºC, while that of the mixture was 36ºC.
(i) Other than increase in temperature, state and explain the observations which were made during the reaction.
(ii) Calculate the heat change during the reaction. (Specific heat capacity of the solution = 4.2Jgˉ¹Kˉ¹ and the density of the solution = 1g/cm³.
(iii) Determine the molar heat of displacement of copper by zinc. (Zn = 65).

  

Answers


Maurice
(i) - The blue colour of the solution fades.
- A brown solid is deposited.
The blue Cu2+ ion are discharged to copper metal which is brown.

(ii) Temperature change = 36 – 24 = 12ºC
Heat change = 25 x 4.2 x 12
= 1260 Joules

(iii) Q69620191034.png
maurice.mutuku answered the question on September 6, 2019 at 07:36


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