Question

The degree of freedoms for Sulphur system at the triple point is:
A.0
B.-1
C.2
D.+1

Answer 1

Hint:When one degree of freedom, \[F = 1\] are univariant and those with two degrees of freedom where \[F = 2\] are bivariate. Here we find the degree of freedom for the Sulphur system at the triple point by the calculation. Degree of freedom is the number of molecules in the gas phase that move, rotate or vibrate. It is an independent parameter in the formal description.

Complete step by step answer:
The degree of freedoms for the Sulphur system at the triple point is found by the phase rule.
Phase rules predicting the equilibrium relations present as a functional of physical conditions such as pressure and temperature.
Now we discuss about the degree of freedom as below,
At the triple point \[P = 3\] , \[C = 1\]
So, calculation is given below,
 \[\begin{array}{*{20}{l}}
  {F + P = C + 2} \\
  {F + 3 = 1 + 2} \\
  {F = 0}
\end{array}\] .
Therefore, Option (A) is the correct answer.

Additional information:
The Sulphur system shows the conditions of temperature and pressure at which phases coexist at equilibrium. It is equal to the number of components minus the number of phases which comes from variable temperatures and pressure.

Note:The temperature and pressure at which different three phases which are gaseous, liquid and solid phases. It is a particular substance that can coexist in equilibrium. Number of components is 1, so the number of phases is 3. Here we remember the number of P and C, which is useful to find the degree of freedom. Sulphur melts, then the triple point for ${S_m} \rightleftharpoons {S_1} \rightleftharpoons {S_g}$ .