Consider the following statements. Which of the following statement(s) is/are true when a mixture of NaCl and K2Cr2O7 is gently warmed with concentrated H2SO4?Deep red colour vapours are observedVapours when passed into NaOH solution, gives a brown solutionSmall amount of chlorine gas is releasedIn product formed oxidation state of chromium is same as that in reactant

The correct statements when a mixture of NaCl and K2Cr2O7 is gently warmed with concentrated H2SO4 are:

1. Deep red colour vapours are observed: This is true. When K2Cr2O7 is heated with concentrated H2SO4, it produces CrO3 which is a deep red vapour.

2. Vapours when passed into NaOH solution, gives a brown solution: This is also true. The deep red vapours of CrO3 when passed into NaOH solution, it forms chromate which is a brown solution.

3. Small amount of chlorine gas is released: This is true. When NaCl is heated with concentrated H2SO4, it produces HCl gas. However, in the presence of K2Cr2O7, the HCl is oxidized to Cl2, a greenish-yellow gas.

4. In product formed oxidation state of chromium is same as that in reactant: This is false. In K2Cr2O7, the oxidation state of chromium is +6. When it is heated with concentrated H2SO4, it forms CrO3, where the oxidation state of chromium is +6. However, when the vapours are passed into NaOH solution, it forms chromate, where the oxidation state of chromium is +3. Therefore, the oxidation state of chromium changes in the product.