For a first order reaction with half-life of 126 seconds, a) Calculate the rate constant for the reaction. (2 points)b) How much time would the reaction take for 12.5% to be left remaining? (1 points) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

Consider the reaction at equilibrium:         I2(g) + Cl2(g) ⇌ 2 ICl(g)         Kc = 0.11 Calculate the equilibrium concentration (in M) of ICl when 0.45 mol I2 and 0.45 mol Cl2 are initially mixed in a 2.0L flask. (5 pts.) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

Consider the reaction at equilibrium:         Fe3+(aq) + SCN-(aq) ⇌  FeSCN2+(aq)          A sollution is made containing an initial [Fe3+] of 1.11 ×10-4 M and an initial [SCN-] of 1.00 ×10-4 M. At equilibrium [FeSCN2+] = 1.70 ×10-4 M. Calculate the value of the equilibrium  constant (Kc) for the above reaction. (5 pts.) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

Write an equilibrium expression (Kc or Kp) for each chemical reaction. (4 pts.) a) (Kc) 2H2O(l) ⇌H3O+(aq) + OH-(aq) b) (Kp) 2Ag2O(s) + H2(g) ⇌ 4Ag(s) + 2H2O(g) c)  (Kc) HCO3-(aq) + H+(aq) ⇌ H2O(l) + CO2(g)         d)  (Kp) C(s) +CO2(g) ⇌2 CO(g) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

Consider the reaction at equilibrium:         Fe3+(aq) + SCN-(aq) ⇌  FeSCN2+(aq)          A sollution is made containing an initial [Fe3+] of 1.11 ×10-4 M and an initial [SCN-] of 1.00 ×10-4 M. At equilibrium [FeSCN2+] = 1.70 ×10-4 M. Calculate the value of the equilibrium  constant (Kc) for the above reaction. (5 pts.) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

Consider the reaction. (Write your answer including its units in the textbox below.  specify answer for part a. and part b.)                      2 N2O(g) → 2 N2(g) + O2(g) a. Express the rate of the reaction in terms of the change in concentration of each of the reactants and products. (2 pts.) b. If 0.015 mol of N2 is produced in a 0.500 L vessel within 15 seconds, what is the rate of reaction with respect to N2 (ΔN2/Δt)? How about with respect to O2? (4 pts) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

Consider the reaction:        2 H2S(g) ⇌ 2 H2(g) + S2(g)                   Kp = 2.40 x 10-4 @ 1073K A reaction mixture contains 0.112 atm H2, 0.055 atm S2, and 0.445 atm H2S. a) Calculate the reaction quotient (Qp) (3pts)    b) What direction is the reaction going. (Left      Right     Neither) (2pts) c) Calculate the Kc for the reaction given above. (2 pts) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

Consider the reaction:        2 H2S(g) ⇌ 2 H2(g) + S2(g)                   Kp = 2.40 x 10-4 @ 1073K A reaction mixture contains 0.112 atm H2, 0.055 atm S2, and 0.445 atm H2S. a) Calculate the reaction quotient (Qp) (3pts)    b) What direction is the reaction going. (Left      Right     Neither) (2pts) c) Calculate the Kc for the reaction given above. (2 pts) **This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

  Based on the produced graph data shown above for a reactant in a reaction, answer the following questions.      a) Based on the information given, what reaction order do you expect for the reactant? (2 points)      b) What would be the k value for this reaction? Include the units. (2 points)      c) What would the final concentration be after 75 seconds? (3 points)**This question copyright of Dr. Simon Tang @ Valencia College. No permission for redistribution of this question.

The following question refers to the essential steps in meiosis described below. 1. formation of four new nuclei, each with half the chromosomes present in the parental nucleus 2. alignment of homologous chromosomes at the metaphase plate 3. separation of sister chromatids 4. separation of the homologs; no uncoupling of the centromere 5. synapsis; chromosomes moving to the middle of the cell in pairs Which of the steps take(s) place in both mitosis and meiosis?