Equilibrium
Topics
- Dynamic equilibrium and physical equilibria, Henry's law
- Law of chemical equilibrium, Kp and Kc
- Delta G and equilibrium, factors affecting equilibrium, Le Chatelier's principle
- Electrolytes and acid-base concepts (Arrhenius, Bronsted-Lowry, Lewis)
- Ionization constants, ionization of water, pH scale
- Common ion effect, hydrolysis of salts
- Solubility product
- Buffer solutions
Chapter tests
See all →Top questions
See all →- Higher yield of NO in N_2(g) + O_2(g) ⇌ 2NO(g) can be obtained at[Δ H of the reaction = + 180.7 kJ mol^-1]A. higher temperatureB. lower temperatureC. higher concentration of N_2D. higher concentration of O_2Choose the correct answer from the options… Answer: 4. A, C, D only Key idea: Le Chatelier's principle. Δ H>0 (endothermic): higher temperature favours NO, so A is right and B is wrong... 1
- For the reaction A(g) ⇌ 2B(g), the backward reaction rate constant is higher than the forward reaction rate constant by a factor of 2500, at 1000 K.[Given : R = 0.0831 L atm mol^-1 K^-1]K_p for the reaction at 1000 K is Answer: 3. 0.033 Key idea: K_c=k_f/k_b and K_p=K_c(RT)^(Δ n) . k_b=2500 k_f , so K_c=1/2500=4×10⁻⁴ . Δ n=2-1=1 ; RT=0.0831×1000=83.1 . K_p=4... 1
- Phosphoric acid ionizes in three steps with ionization constant values K_a_1, K_a_2 and K_a_3, respectively, while K is the overall ionization constant. Which of the following statements are true?A. K = K_a_1 + K_a_2 + K_a_3B. H_3PO_4 is a stronger a… Answer: 4. A, B and C only Key idea: overall K=K_(a_1)K_(a_2)K_(a_3) , and each successive ionization is harder. A true: taking logs, log K=... 1
- Consider the following reaction in a sealed vessel at equilibrium with concentrations of N_2 = 3.0×10^-3 M, O_2 = 4.2×10^-3 M and NO = 2.8×10^-3 M.2NO_(g) ⇌ N_2(g) + O_2(g)If 0.1 mol L^-1 of NO_(g) is taken in a closed vessel, what will be degree of… Answer: 1. 0.717 Key idea: get K_c from the first data set, then use it for the new mixture. K_c=[N₂][O₂]/[NO]²=frac(3.0×10⁻³)(4.2×10⁻³)(2.8... 1
- The Henry's law constant (K_H) values of three gases (A, B, C) in water are 145, 2×10^-5 and 35 kbar, respectively. The solubility of these gases in water follow the order: Answer: 3. B > C > A Key idea: by Henry's law p=K_Hx , so a larger K_H means lower solubility. K_H : B ( 2×10⁻⁵ ) < C (35) < A (145) kbar. S... 1
- For the reaction 2A ⇌ B + C, K_c = 4×10^-3. At a given time, the composition of reaction mixture is : [A]=[B]=[C]=2×10^-3 M.Then, which of the following is correct? Answer: 4. Reaction has a tendency to go in backward direction. Key idea: compare the reaction quotient Q_c with K_c . Q_c=[B][C]/[A]²=frac(... 1