Question

Iron is dropped in very dil. $HN{O_3}$ it gives
A.Ferric nitrate
B.Ferric nitrate and $N{O_2}$
C.Ferrous nitrate and ammonium nitrate
D.Ferrous nitrate and nitric oxide

Answer 1

Reactants: The compounds which react with each other to form a new compound, are known as reactants.
Products: The compounds which are formed when reactants react with each other, are known as products.

Complete step by step solution:
Here we have to find the product when iron is dropped very dil. $HN{O_3}$. The reaction is as follows:
$4Fe + 10HN{O_3} \to 4Fe{(N{O_3})_2} + 3{H_2}O + N{H_4}N{O_3}$. $Fe{(N{O_3})_2}$ is known as ferric nitrate. $N{H_4}N{O_3}$ is known as ammonium nitrate.
Here we are getting ferrous nitrate and ammonium nitrate along with water as products.

Hence option C is correct.

Additional information:
Generally the compound whose oxidation number increases during the reaction is known as oxidised compound and the compound whose oxidation number decreases during the reaction is known as reduced compound.
Now let us first talk about the oxidations number of elements in the compounds given in the reaction.
Oxidation number of an element: It is defined as the total number of electrons that an atom accepts or loses in order to make a chemical bond which results in the formation of a chemical compound.
Oxidation: The compound which loses the electron during the reaction or the compound whose oxidation number increases during the reaction.
Reduction: The compound which gains the electron during the reaction or the compound whose oxidation number decreases during the reaction.
Here in the reaction iron is an oxidised compound (because oxidation number increases) and nitrogen acts as reduced compound (because oxidation number decreases).
There is another definition of defining oxidised and reduced compounds as well.
Oxidized compound: The compound to which oxygen is added during the reaction, is known as oxidized compound.
Reduced compound: The compound from which oxygen is removed during the reaction, is known as reduced compound.

Note:
If we use concentrated nitric acid in place of dilute acid then there will be no reaction between iron and concentrated nitric acid.
Generally the compound which is oxidised in the reaction will act as reducing reagent (which oxidises the other compounds) and the compound which is reduced in the reaction will act as oxidising reagent (which reduces the other compounds) for the reaction.