Discussion
For the following reaction,
2 Pb3O4(s) \(\rightleftharpoons\) 6 PbO(s) + O2(g)
The correct option showing the number of phases (P), number of components (C) and degrees of freedom (F) is
Answer: A
The correct option is P = 3, C = 2, F = 1.
- Phases: Pb3O4(s), PbO(s) and O2(g). Each solid is a separate phase and the gas is one more, so P = 3.
- Components: three species linked by one equilibrium, so C = 3 - 1 = 2 (for example PbO and O2).
\[ F = C - P + 2 = 2 - 3 + 2 = 1 \]
The system is univariant, like CaCO3 decomposing: fixing the temperature fixes the equilibrium O2 pressure. P = 3, C = 3 ignores the reaction relation. The options with P = 2 count the two solids as one phase, but two distinct solids are always two phases.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development