Consider the following statements pertaining to the properties of perfect, non reacting gas mixtures:
1. The total volume of a mixture is the sum of partial volumes at the same pressure and temperature
2. The entropy of a mixture of gases is the same as the entropies of the constituents
3. The total pressure of a mixture of gases is the sum of the partial pressures of the substances
4. The mole fraction of a mixture of gases is equal to both pressure and volume fraction
Which of the above statements is/are correct?
(A) 1, 2, 3 and 4 (B) 1, 2 and 3 only
(C) 1, 2 and 4 only (D) 3 and 4 only