Exam 2

What is the pH when the [H+]=2.51e-11

10.6

What is the [OH-] when the pH=8.4?

2.5e-6M

What is the Ka when the pKa is -1.4?

25

What is the pH when the [OH-]=2.51e-11?

3.40

What is the pKa when the Ka=1.8e-5?

4.7

What is the pH when the [H+]=3.98e-6?

5.40

What is the pOH when the [H+]=3.98e-6

8.60

Which of the following compounds is the strongest Bronsted base? CH3-, NH2-, OH-, F-

CH3-

Which of the following compounds is the strongest Bronsted base? H2PO4-, HSO4-, NO3-, CH3COO-

CH3COO-

Which of the following compounds is the strongest Bronsted acid? CH4, NH3, H2O, HF

HF

Which Bronsted acid (H2O or H2S(aq)) is the stronger acid and why?

H2S is the stronger acid because there is a longer bond length between the sulfur and hydrogen.

Which of the following compounds is the strongest Bronsted acid? H3PO4, H2SO4, HNO3, CH3COOH

H2SO4

Which Bronsted acid (HCl or H2S(aq)) is the stronger acid and why?

HCl is the stronger acid because chlorine has a greater electronegativity than sulfur.

Which of the following is the strongest Bronsted base? NaCH3, NaOH, NaF, NaNH2

NaCH3

Base...

conjugate acid

Acid...

conjugate base

pKa decreases,

down the periodic table

Ka>1 when

products occur in the majority

Ka<1 when

reactants occur in the majority

The lower the pKa,

the stronger the acid.