Lecture 5

Question 1

What is the van’t Hoff factor and when do we use it

Answer 1

i = moles of particles in solution/moles of solute dissolved
–> ex: For NaCl, i = 2 (Na+, Cl-)
–> electrolytes don’t completely dissociate (separate)

Question 2

What are the freezing and boiling point, and osmotic pressure equations with the van’t Hoff factor

Answer 2

1. delta(T) = imK
2. pi = iMRT

Question 3

What is chemical equilibrium?

Answer 3

State where concentrations of all R and P remain constant (don’t stop, are just constant)
–> forwards and backwards reactions going at the same speed
–> DOESN’T SAY ANYTHING ABOUT AMOUNT ON EACH SIDE
–> no changes are perceivable (reactions continually occurring tho)

Question 4

Where does the equilibrium lie if the reaction favours the reactants (R)

Answer 4

To the left

Question 5

Where does the equilibrium lie is the reaction favours the products (P)

Answer 5

To the right

Question 6

What factors does the side the equilibrium lies on depend on?

Answer 6

1. Initial conc.
2. Relative E of R and P
3. Relative degree of organization

Question 7

What is the equilibrium constant equation

Answer 7

K = [P]/[R]

NOTE: for reverse reaction: K’ = 1/K

Question 8

How are the R and P related depending on K

Answer 8

1. K = 1 –> [R] = [P]
2. K > 1 –> [R] < [P] (lies to the right - must shift left)
3. K < 1 –> [R] > [P] (lies to the left - must shift right)