AIIMS2019ChemistryChemical Kinetics
The decomposition of NH ₃ on platinum surface is zero order reaction. The rates of production of N ₂ and H ₂ are respectively (k=2.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ )
Options
- A7.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ ; 2.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹
- B2.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ ; 7.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹
- C5.0 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ ; 2.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹
- D2.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ ; 5.0 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹
Correct answer
B. 2.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ ; 7.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹
Step-by-step solution
For the reaction, 2 NH ₃ N ₂+3 H ₂ From equation (i) and (ii) Rate of production of N ₂, d [ ~N ₂ ] d t =k=2.5 10⁻⁴ ~mol ~L ~L ⁻¹ ~s ⁻¹ From equation (iii) Rate of production of H ₂, d [ H ₂ ] d t =3 k aligned & =3 2.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ & =7.5 10⁻⁴ ~mol ~L ⁻¹ ~s ⁻¹ aligned