103B PS 4

# 103B PS 4 - problem set 1 Page 1 CHEMISTRY 103B Sections...

This preview shows pages 1–2. Sign up to view the full content.

problem set 1 4/10/2008 12:15:53 AM http://www.chem.arizona.edu/~kellerp/ps-answers/PS4an/PS4an.htm CHEMISTRY 103B, Sections 3-4 and 7-8 Problem Set 4: 16 Points Answer Key Problem1. ( three points ) Thisdealswitha water solutioninwhichthe initial concentration of the weak acidHA(aq) is0.50 mol/L. Theinitialconcentrationsof H 3 O + (aq) and A - (aq) are both zero. For thisacidK a = 7.0 x 10 -6 . HA(aq) H + (aq) A - (aq) Initial 0.50 0 0 Change -x +x +x Equilibrium [0.50 x] [x] [x] (a) Whatisthe equilibriumconcentrationof the weak acid? [HA} = 0.50 x = 0.50 0.0019 = 0.50 mol/L (two sigfigs) (b) Whatisthe equilibriumconcentrationof hydroniumion? [H + ] = x = 0.0019 mol/L (c) Whatisthe equilibriumconcentrationof the conjugatebase of the acid? [A - ] = x = 0.0019 mol/L Problem2. ( three points ) Thisproblemdealswitha water solutionof a weak base. The initialconcentrationof the base is0.010 mol/L. Theinitialconcentrationsof hydroxideion and the conjugateacidof the base are both zero. For thisbase K b = 6.0 x 10 -2 . B(aq)

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 4

103B PS 4 - problem set 1 Page 1 CHEMISTRY 103B Sections...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online