Question

you might have seen a thermos flask used for keeping tea ,coffee, milk,etc.hot or a sherbet cold for a long time .What is its structure and how does it function?​

Answer 1

Answer:

When an iron nail is dipped in copper sulphate solution, a brown coating of copper is formed in the surface of iron and the colour of copper sulphate solution changes from blue to pale green. The reaction shows that iron is more reactive than copper because it displaces copper from the copper sulphate solution.

Answer 2

Answer:

Explanation:

The silver coated surface becomes shiny, so it reflects all the heat inside the wall, and it does not allow the heat to go out. And the layer of glass wall thermo flask is thin, so it prevents the loss of heat by conduction. Therefore, the thermo flask keeps cold liquid cold and hot liquid hot.