# Chemistry Class 11 NCERT Solutions Chapter 7 Equilibrium Part 12

Q: 33. The value of for the reaction

Is at If the equilibrium concentration of in air at is what is the concentration of?

The given reaction is:

Then,

It is given that

Then, we have,

Hence, the concentration of

Q: 34. The reaction is at equilibrium at 1300 K in a 1L flask. It also contains 0.30 mol of CO, 0.10 mol of and 0.02 mol of and an unknown amount of in the flask. Determine the concentration of in the mixture. The equilibrium constant, for the reaction at the given temperature is 3.90.

Let the concentration of methane at equilibrium be X.

It is given that

Therefore

Hence, the concentration of at equilibrium is

Q: 35. What is meant by the conjugate acid – base pair? Find the conjugate acid/base for the following species

Answer: A conjugate acid-base pair is a pair that differs only by one proton.

The conjugate acid-base for the given species is mentioned in the table below.

Q: 36. Which of the following are Lewis acids?

Answer: Lewis acids are those acids, which can accept a pair of electrons. For example, and are Lewis acids.

Q: 37. What will be the conjugate bases for the Bronsted acids

Answer: The table below lists the conjugate bases for the given Bronsted acids.

Q: 38. Write the conjugate acids for the following Bronsted bases:

Answer: The table below lists the conjugate acids for the given Bronsted bases

Q: 39. The species: and can act both as Bronsted acids and bases. For each case give the corresponding conjugate acid and base.