18.1.2 Bond Strengths

Question 1

Most acid-base reaction mechanisms are based on the breaking / forming of polar bonds. How can the relative electronegativity of hydrogen and the atom to which it is attached in an acid be described?

Answer 1

Hydrogen is usually less electronegative than the atom to which it is attached in an acid.

Question 2

As one looks at the elements of the periodic table from left to right, what trend would one expect to find among acids containing these elements?

Answer 2

Increasing levels of electronegativity

Question 3

As one considers elements going down the periodic table, electronegativity tends to ______.

Answer 3

decrease

Question 4

Which acid is the strongest?

Answer 4

Hydroiodic

Question 5

In comparing the relative acidities of the hydrogen halides (HF, HCl, HBr, HI), what is the dominant factor in determining acidic behavior going down the group?

Answer 5

The decreasing bond strength as you look down the periodic table

Question 6

Which acid would have the smallest power of dissociation constant?

Answer 6

HF

Question 7

What acidity trend exists among the elements in the periodic table from bottom to top?

Answer 7

Decreasing levels of acid strength

Question 8

If hydrobromic acid were homolytically cleaved, how many electrons would go to the hydrogen atom?

Answer 8

1

Question 9

What is the relationship between the degree of polarization and the degree of electronegativity of the bond between hydrogen and an electronegative atom?

Answer 9

The larger the degree of polarization of the bond between hydrogen and an electronegative atom, the larger the degree of electronegativity.

Question 10

Which promotes the heterolytic cleavage of certain chemical bonds?

Answer 10

Increased polarization