Assignment 8

Question 1

equilibrium

Answer 1

when the forward and reverse reactions have rates such that the concentrations of reactants and products are constant

• no free energy (ΔG = 0, TΔS = ΔH)
• has to be reversible
• V, P, T can change
• closed system
• changed by ΔT Δconcentration ΔP

Question 2

equilibrium expression

Answer 2

the relationship of the forward and reverse rates

• k_eq = [prod]/[react]
• k_eq > 1 –> favors [prod]
• k_eq < 1 –> favors [react]

Question 3

reversible

Answer 3

when ΔG = 0 at some T

• has the potential to be at equilibrium

Question 4

concentration

Answer 4

stuff per total stuff

• measured amount/total amount

Question 5

molarity (M)

Answer 5

M = measured moles/L of total material

Question 6

particles per million (ppm)

Answer 6

ppm = # of particles involved/1,000,000 particles (mg/L)

Question 7

mechanism

Answer 7

series of bimolecular steps

Question 8

Boltzmann Distribution Model

Answer 8

shows the distribution of energy of particles in a system (explains why K changes with T)

Question 9

rate

Answer 9

concentration change of reactant per time

• r = Δ[reactant]/sec = ΔM/Δt
• impacted by T, state of reactants/surface area, catalysts and concentration

Question 10

rate law

Answer 10

rate = kΔ[reactant]

• k: rate “constant” (different for every reaction), represents the likelihood that two molecules will react
  
  • proportional to T

Question 11

order of a reaction

Answer 11

how much the rate of the reaction depends on the concentration

• often the coefficient (from the reaction equation) will be the order of that reactant
• correlates with rate (higher order = higher rate)
• 0th order means the concentration doesn’t affect the rate

Question 12

how to get order of a reaction from data

Answer 12

1) the coefficient (stoich)
2) take concentration data - order of a reactant = (M_f/M_i)/(r_f/r_i)

Question 13

what 2 things do reactions need to occur (collision theory)

Answer 13

energy and proper orientation