Exam 2

Question 1

Spectator ions

Answer 1

Ions that do not change during the equation

Question 2

Net ionic equation

Answer 2

Shows only the parts of the reaction that are changing (overall reaction)

Question 3

detailed ionic equation

Answer 3

Shows all parts of equation

Question 4

Acids

Answer 4

• acidic hydrogens are bonded to electronegative elements
• X-H bonds are weakens by reaction
• conjugate base is stable
• more electronegative = more acidic

Question 5

Base

Answer 5

• have lone pair of electrons
• should be relatively stable when forming bonds
• the less electronegative the more basic

Question 6

Acid strength depends on…

Answer 6

• the enthalpy change (strength of bond and stability of conjugate base)
• the entropy change
• increases down a group due to both
• increases across a row bc of electronegativity

Question 7

Bond energies

Answer 7

• The energy it takes to break a bond in gas phase
• averages!!
• only in gas phase
• bonds don’t break and form in sequence

Question 8

Enthalpic and entropic effect

Answer 8

bond strength increases down a group

• orbitals overlap less; weakens bonds
• entropy decreases when they solvate in small ions

Question 9

Resonance structure

Answer 9

When negative charge is split, increases entropy and enthalpy
(A mule)
-strengthens acid
-weakens conjugate base(more stable)

Question 10

Ph

Answer 10

-log[H3O+]
(1x10^-7)
-decrease in acidity
-depends on temp

Question 11

Oxidation number rules

Answer 11

• element is always zero
• ion is always the charge of the ion
• oxygen is almost always -2
• H is usually +1
• put all valence e on most electronegative and count charge
• just helps with what atoms loose what in a reaction

Question 12

Nucleophile

Answer 12

• nucleus loving Lewis base

- partially negative

Question 13

Electrophile

Answer 13

Electron loving Lewis acid

Carbon only

Question 14

Electronegativity

Answer 14

Ability of an element to attract electrons in a bond

-increases across decreases down

Question 15

Formal charge

Answer 15

Valence electrons minus number of bonds minus nonbonded electrons

Question 16

Calorimetry at constant P

Answer 16

-to find thermal energy during process
-need insulated container
-mass x specific heat x temp change
(Typically in solution)

Question 17

Specific heat

Answer 17

Heat to raise 1g by 1 C

Question 18

ATP hydrolysis

Answer 18

Common driver for unfavorable reactions bc the energy change is negative
-electrophile-nucleophile interaction

Question 19

Titration

Answer 19

Analysis of unknown solution using a solution of known concentration

• use stoic
• usually acid/base reaction

Question 20

Bond dissociation energy

Answer 20

The energy required to break a bond in the gas phase