University:
Kentucky State University
Course:
CHE 101 | General Chemistry I
Academic year:

2019
Views:

345

Pages:

25
Author:

Lamghari6kx

What is a conjugate acid-base pair in the following equilibrium? H2O(I)+ HPO4^-2(aq) <--> - - H2PO4 (aq) +OH (aq) Select one: - a- H2O is an acid and OH is its conjugate base. b- HPO4^-2 is acid and H2O is its conjugate base. - c- HPO4^-2 is acid and H2PO4 is its conjugate base. d-HPO4^f-2 is acid and OH is its Conjugate base. e- H2O is acid and HPO4^-2 is its conjugate base. If the Ka of NH4 is 5.6 x 10^-10 and the Kb for F is 14 x 10^-11 When the NH4F salt is dissolved in water, the solution will be: a- Basic b- Cannot be determined from the data given. c- Acidic d- Neutral What is the pH of a solution that is 0.140 M in acetic acid, HC2H3O2 and 0.500 M in sodium acetate, NaC2H3O2, at 25 °C? Ka for acetic acid is 1.80x 10^-5 Select one: a- 5.47 b-5.01 c- 5.30 d-6.03 e-4.78 The Ka for hydrofluoric acid (HF) is 5.7 x 10-5. What is kp for the fluoride ion? Select one: a- 1.1x 10^-9 b- 1.8 x 10^-10 c- 1.5 x 10^-11 d-1.1x 10^-11 e- 1.8 x 10^-11 What is the pH of the final solution when 25.0 mL of 0.0230M HCI has been added to 35.0 mL of 0.0400 M HCI at 25°C? Select one a-2.16 b- 1.48 c- 2.45 d-3.92 e- 1.72 If you have prepared 1.0 L of a HF buffer solution that having the concentrations: - [HF] = 0.24 M, [F ] = 0.16 M What is the pH of the buffer solution after adding 0.05 M HCI ? pka=4.75 for HF. a- 4.33 b- 4.57 c-5.17 d-4.75 e-4.41 What is the pH of a solution that is 0.140 M in acetic acid, HC2H3O2, and 0.750 Min sodium acetate, NaC2H3O2, at 25 °C? Ka for acetic acid is 1.80 x 10-5. Select one: a- 5.01 b-4.78 c- 5.30 d-5.47 e-6.03