Gen Chem / O Chem

Question 1

If a 1L box has a partial pressure of 2 atm N2 and another 1L box has a partial pressure of 1 atm O2…

Answer 1

when combined, the partial pressure of N2 is 1 atm and O2 is 0.5 atm

Question 2

PE of charges

Answer 2

U = kQq/r
smaller r = greater PE for like charges
bigger r = greater PE for opposite charges

Question 3

ionic radii

Answer 3

• for metals, it increases to the left and down b/c metals lose electrons
• nonmetals: increases right and down

atomic radii- increases to the left and down

Question 4

imine

Answer 4

C=N

ketone + NH3

Question 5

cyanohydrins

Answer 5

HCN + ketones

• stable
• chiral

Question 6

Electron affinity

Answer 6

-E released when gains electron

Question 7

Ionization E

Answer 7

-E required to take an electron from a gas

Question 8

Work function

Answer 8

-E required to steal electron from metallic surface

Question 9

If PCB in water is 50 parts per trillion, and I drink 2 L of water per day for 30 days…

Answer 9

50 g PCB / 10^12 g water (1 g H2O / 1 mL H2O)
(1000 mL H2O) (1 L H2O) (2 L H2O / day) (30 days)

Pay attention to units

Question 10

Q > Keq

Answer 10

When Q > Keq, reverse rxn is favored

• so deltaG > 0
• there are more products than at equilibrium but not necessarily more PDTs than reactants

deltaG = RTln(Q/Keq)

Question 11

Is NaCl soluble in ether?

Answer 11

No

Question 12

What does NaCl in water do to the solubility of other things in water?

Answer 12

It decreases it

Question 13

Evaporating off a liquid from another liquid is basically

Answer 13

distillation

Question 14

Boiling point

Answer 14

Vapor pressure = atmospheric pressure

• adding NON VOLATILE solute decreases VP which increases BP (Raoult’s law) b/c is VP goes down, more E / temp will be needed to make VP then reach ambient / incident P
• adding a volatile solute would increase the VP as opposed to pure VP before anything was added