CHM 152 Exam 3

What is the conjugate?

100

HCl

Cl-

200

OH-

H2O

300

CH₃COOH

CH₃COO-

400

NH₃

NH₄+

500

CH₃CH₂NH₂

CH₃CH₂NH₃+

What kind of salt is it?

100

NaBr

RbCl

NaF

Neutral

Neutral

Basic

200

Na₂CO₃

KI

Basic

Neutral

300

NH₄Br

CaCl

Acidic

Acidic

400

CsCl

BeBr

Neutral

Acidic

500

MgClO₄

FeNO₃

BaSO₄

Acidic

Acidic

Neutral

Stronger acid? Why?

100

CH4 or NH3

NH3; electronegativity

200

HCl or HBr

HBr; atomic radius

300

H2SO4 or H3PO4

H2SO4; electronegativity

400

HBrO or HBrO2

HBrO2; more oxygens= more electron density away from H

500

Chloric acid or chlorous acid?

Chloric acid, more oxygens

Fill in the blank

100

_______ can be an acid, or a base

water

200

Bases ____ a proton from an acid

accept

300

A ______ acid is more likely to have a lower pH value than a _____ acid

strong; weak

400

______ bases release an OH- into solution, while ______ bases accept a H+ from an acid

arrhenius; bronsted

500

HClO₄ is a ______ acid than H₂SO₄, because of ________

stronger; electronegativity

Calculations

100

Calculate the [H3O+] concentration of 0.72 HCl.

0.72

200

Calculate the pH of 0.72 HCl.

0.14

300

Calculate the pH of a buffer solution with 0.25 M NaCN and 0.17 M HCN at 25 degrees Celsius. 

Ka=6.4 E -4

3.4

400

Calculate the ratio of base to acid needed to make a CH₃COOH/NaCH₃COOH buffer with a pH of 4.84.

1.25:1

500

Calculate the pH of a buffer solution with 0.36 M NH3 and 0.27 M NH4Cl at 25 degrees Celsius in a 1 L solution Kb= 1.57 E -5.

Calculate the pH after adding 0.1 mol LiOH. Assume no change in volume. Then, calculate the change in pH. Make the chemical equation and ice tables for both steps.

9.32

9.63

change= 0.32