Q. 594.3( 7 Votes )
A non-metal A which is the largest constituent of air, when heated with H2 in 1:3 ratio in the presence of catalyst (Fe) gives a gas B. On heating with O2 it gives an oxide C. If this oxide is passed into water in the presence of air it gives an acid D which acts as a strong oxidising agent.
(a) Identify A, B, C and D.
(b) To which group of periodic table does this non-metal belong?
The non-metal A is nitrogen (N2). It forms the largest constituent of air, i.e., 78%. When N2 is heated with H2 in 1:3 ratio in presence of iron (Fe) as catalyst, it forms ammonia gas (NH3). This is known as Haber process. Thus the gas B is ammonia. When ammonia is heated with O2, it forms nitric oxide (NO). NO further gets oxidized to NO2 by O2. Thus, oxide C is NO2 (nitrogen dioxide). When this oxide reacts with water in the presence of air (O2), it gives nitric acid. Thus acid D is nitric acid which is a strong oxidizing agent. The chemical reactions involved are as follows:
(b) Nitrogen belongs to Group 15 of periodic table because nitrogen has 5 valence electrons (electronic configuration is of N is 2, 5).
Rate this question :
During the reaction of some metals with dilute hydrochloric acid, following observations were made.
i. The temperature of the reaction mixture rises when aluminium (Al) is added.
ii. The reaction of sodium metal is found to be highly explosive.
iii. Some bubbles of a gas are seen when lead (Pb) is reacted with the acid.
Explain these observations giving suitable reasons.Xam idea - Science
State which of the following chemical reaction will take place, giving a suitable reason for each.
Zn(s)+CuSO4(aq)→ ZnSO4(aq) + Cu(s)
Fe(s)+ ZnSO4(aq) → FeSO4(aq)+Zn(s)
Zn(s)+ FeSO4→ ZnSO4+Fe(s)Xam idea - Science
i. Why potato chips manufacturers fill the packet of chips with nitrogen gas?
ii. A student has been collecting silver coins and copper coins. One day she observed a black coating on silver coins and a green coating on copper coins. Which chemical phenomenon is responsible for these coatings? Write the chemical name of black and green coatings.
i. Crystals of copper sulphate are heated in a test for some time.
(a) What is the colour of copper sulphate crystals before heating, and after heating?
(b) What is the source of liquid droplets seen on the inner upper side of the test tube during the heating process?
ii. A metal ‘X’ when dipped in an aqueous solution of aluminium sulphate no reaction is observed whereas when it is dipped in an aqueous solution of ferrous sulphate, the pale green solution turns colourless. Identify metal ‘X’ with reason.Xam idea - Science
What is observed when a solution of sodium sulphate is added to a solution of barium chloride taken in a test tube? Write equation for the chemical reaction involved and name the type of reaction in this case.Science - Board Papers