Question
The presence of carbon in an organic compound can be shown by
A.
heating the compound with sodium
B.
heating the compound with cupric oxide
C.
heating the compound on Bunsen flame
D.
heating the compound with magnesium
Answer :
heating the compound with cupric oxide
Solution :
Compound when heated with $$CuO$$ reduces $$CuO$$ to $$Cu$$ and oxidises $$C$$ to $$C{O_2}$$ which turns lime water milky.
$$\eqalign{
& C + 2CuO \to 2Cu + C{O_2} \cr
& C{O_2} + Ca{\left( {OH} \right)_2} \to \mathop {CaC{O_3}}\limits_{{\text{(Milky)}}} + {H_2}O \cr} $$