Question

In a reaction 3A + B, A,B, [NCERT Pg. 20]
If 180 atoms of A and 100 molecules of B react,
then
(1) B is limiting reactant and 100 molecules of
A, B, will be formed
(2) A is limiting reactant and 60 molecules of A,B2
will be formed
(3) A is limiting reactant and 180 molecules of
A,B, will be formed​

Answer 1

Answer:

in this reaction A is limiting reactant because for a molecule of B it requires 3 molecule of A so 100 molecules of B requires 300 molecule of A but it is only 180 molecules .so A is limiting reagent .

so option 2 is correct bcs it forms only

60 molecules

Answer 2

In the given reaction 3A + B₂ → A₃B₂,  A will be the limiting reagent

• The reaction given to us is as follows:

                   3A + B₂ → A₃B₂

• We know that:
• Atoms of A = 180
• Molecules of B₂ = 100
• From the equation, we know that for every 3 atoms of A, 1 molecule of B₂ reacts to give us the product.
• So, for every atom of A, 1/3 molecules of B₂ will react, thus for 180 atoms of A, 60 molecules of B₂ are needed for completion of the reaction.
• B₂ is present in excess and the limiting reagent is A.

Thus, for the given reaction, the correct option is (Option 2) A is the limiting reagent and 60 molecules of A₃B₂will be formed.