Question

No coloured gas is evolved or no colour change is observed when
A) hydrated copper sulphate is heated strongly
B) aqueous solutions of potassium iodide and lead nitrate are mixed together
C) lead nitrate is heated strongly
D) potassium nitrate is heated strongly​

Answer 1

Answer:

d) potassium nitrate is heated strongly

Explanation:

When potassium nitrate is heated, it decomposes into potassium nitrite and oxygen.

So there is no change in colour or no coloured gas (oxygen colourless)