Q: What is the value of $\Delta ng$ for the synthesis of ammonia: $N2(g) + 3H2(g) \rightleftharpoons 2NH3(g)$?

$\Delta ng = \text{Moles of gaseous products} - \text{Moles of gaseous reactants} = 2 - (1 + 3) = -2$.

Question 1

At chemical equilibrium, which of the following statements is correct regarding the rate of forward reaction ($rf$) and backward reaction ($rb$)?

Accepted Answer

At chemical equilibrium, the rate of forward reaction becomes equal to the rate of backward reaction ($rf = rb$), making the equilibrium dynamic in nature.

Question 2

What is the correct mathematical relationship between $Kp$ and $Kc$ for a gaseous reaction?

Accepted Answer

The relationship between $Kp$ and $Kc$ is given by $Kp = Kc(RT)^{\Delta ng}$, where $\Delta ng$ is the change in the number of moles of gaseous products and reactants.

Question 3

What is the value of $\Delta ng$ for the synthesis of ammonia: $N2(g) + 3H2(g) \rightleftharpoons 2NH3(g)$?

Accepted Answer

$\Delta ng = 	ext{Moles of gaseous products} - 	ext{Moles of gaseous reactants} = 2 - (1 + 3) = -2$.

Question 4

According to the Lewis concept, an acid is defined as a substance that:

Accepted Answer

According to Lewis theory, an acid is a species that accepts a pair of electrons, whereas a base is an electron pair donor.

Question 5

Which of the following is the conjugate base of $HCO3^-$?

Accepted Answer

A conjugate base is formed when an acid loses a proton ($H^+$). Removing $H^+$ from $HCO3^-$ yields $CO3^{2-}$.

Equilibrium — CBSE Class 11 Chemistry Important Questions & Revision Notes