Module 5.1 equations

Question 1

What is the rate equation?

Answer 1

rate = K[A]^m [B]^n
K is the rate constant. m and n are the orders with respect to A and B respectively.

Question 2

What is the equation used to figure out the rate constant of a first order reaction?

Answer 2

K = ln(2) / half life

Question 3

lnK graphs, gradient, y intercept and axes?

Answer 3

Axis: x = 1/T , y = lnK
Gradient: -Ea/R
Y-intercept = lnA

Question 4

One of the forms of the arrhenius equation on the data sheet is:
lnk = -EA/RT + lnA
How can this be put into the format of
y = mx + c

Answer 4

lnk = -EA/R * 1/T + lnA

Question 5

What is the equation for the mole fraction?

Answer 5

Mol of specific substance / total mol of mixture

Question 6

What is the equation for partial pressure?

Answer 6

partial pressure = mol fraction * total pressure

Question 7

Equation for pH?

Answer 7

pH= -log([H+])

Question 8

Equation for [H+] in strong acids?

Answer 8

[HA] = [H+]

Question 9

Equation that should be used when directly asked for the equation of Ka in weak acids?

Answer 9

Ka = [H+][A-] / [HA]

Question 10

What is the simplified equation of Ka in weak acids?

Answer 10

Ka = [H+]^2 / [HA]

Question 11

What is the equation for [OH-] in strong bases?

Answer 11

[X Base] = [OH-]

Question 12

What is Kw at room temperature, with units?

Answer 12

1*10^-14 mol^2 dm^-6

Question 13

What is the equation for figuring out [H+] in strong bases?

Answer 13

Kw = 1*10^-14 = [H+][OH-]

Question 14

What is the equation for Ka in a buffer solution?

Answer 14

Ka = [H+][A-] / [HA]

Question 15

What is the equation for pKa?

Answer 15

pKa = -log(Ka)