April 20, 2014

Homework Help: Chemistry(Please check answers)

Posted by Hannah on Monday, April 9, 2012 at 4:12pm.

1)What is the pH of a saturated solution of lead(II) hydroxide? The Ksp= 4.0e-15


4.0e-15 = (x)(2x)^2 = 4x^3

I divided by 4 and took the cube root and got 1.12e-5 but I am not sure I took the cube root correctly.

-log(1.12e-5)= 4.95
14-4.95 = 9.05

The answer choices given are 9.0 and 9.1.

Did I do this correctly?

2) Which pair of mixtures is the most effective buffer system for a pH value of 7.45?

a) Carbonic acid and sodium bicarbonate
b) Sodium bicarbonate and sodium carbonate
c) Sodium dihydrogen phosphate and disodium hydrogen phosphate
d) Hydrogen cyanide and sodium cyanide
e) Ammonia and ammonium chloride

I chose answer c, sodium dihydrogen phosphate abd disodium hydrogen phosphate.

Would you agree?

Thank you for checking my answers.

Answer this Question

First Name:
School Subject:

Related Questions

Chemistry (URGENT) - I have a test soon. If you can help me with these questions...
Chemistry(Please check) - 1) The Ka for acetic acid is 1.8e-5. What is the pH of...
organic chemistry - for each of the following compounds, draw the form in which ...
chemistry - how can i make saturated CuSO4.5H2O saturated solution.Please tell ...
Chemistry - What is the pH of a saturated zinc hydroxide solution?
Chemistry(Please check answers) - 1) The Ka for acetic acid is 1.8e-5. What is ...
Chemistry - a solution saturated in calcium hydroxide(limewater) has a pH of 12....
science - What is the [Pb+2] in a saturated solution of Pb(OH)2 for each of the ...
Chemistry check answers - HA(aq)+ H2O (l) <-> H3O+(aq)+ AŻ (aq) Given the ...
Chemistry- please check my work - Question: When 1.97 grams of Pb(OH)2(s) is ...