Question

9. Which of the following acids is the WEAKEST? The acid is followed by its Ka value. A) HC2H302, 1.8 x 10-5 B) HIO, 2.3 x 10-11 C) HBrO, 2.3 x 10-9 D) HCIO, 2.9 x 10-8 E) C6H5CO2H, 6.3 x 10-5 10. Calculate P [NO]eq, if P [NOCIJeg = 0.33 atm, P [Cl2leq = 0.50 atm, and Kp = 1.9 x 10-2 2 NOCI(g) = 2 NO(g) + Cl2(g) A) 1.7 atm B) 0.0042 atm C) 0.30 atm D) 0.064 atm E) 0.087 atm 11 The following pictures represent the equilibrium state for four different reactions of the type A2+ X2 → 2 AX (X= B, C, D, E). A atoms are unshaded. X atoms are shaded. 800 180118 00 18 00 Ag+B22 AB A2+2 = 2 AC Az +D2 + 2 AD Ay+ E22 AE Which reaction has the smallest equilibrium constant? A) A2 + D2 → 2 AD B) A2+B2 → AB C) A2 + C2 → 2 AC D) A2 + E2 → 2 AE 12. Which of the following are equal for a chemical system at equilibrium? A. the concentrations of reactant and products are equal B. the rate of the forward and reverse reaction C. the rate constants for the forward and reverse reactions are equal D. the time that a particular atom or molecule spends as a reactant and product are equal E, all of the above are equal 13. What is An for the following equation in relating Kc to Kp? A) 3 N204(9) = 2NO2(g) B) 1 C)-2 02 E1

Answer 1

9)

Ka is acid dissociation constant.

The acid with smallest value of Ka is weakest.

Ka is smallest for HIO

So, HIO is weakest acid

Answer: B

10)

Kp is defined as pressure of product by pressure of reactant with each pressure term raised to power that is equal to its stoichiometric coefficient in balanced equation

Use:

Kp = p(NO)^2 * p(Cl2) / p(NOCl)^2

1.9*10^-2 = p(NO)^2 * 0.50 / 0.33^2

p(NO)^2 = 4.138*10^-3

p(NO) = 0.064 atm

Answer: D

Only 1 question at a time please