Thermochemistry

Question 1

1 J (unit conversion)

Answer 1

1 Nm = 1 kgm^2/s^2

Question 2

I calorie (cal)

Answer 2

4.184 J

Question 3

1 Calorie (Cal)/1 kilocalorie (kcal)

Answer 3

4184 J

Question 4

I kilowatt-hour (kWh)

Answer 4

3.60 x 10^6 J

Question 5

Change in internal E (delta E)

Answer 5

delta E = q + w (heat plus work)

[delta E sys = - delta E surr]

Question 6

Heat equation (J)

Answer 6

q = m * Cs * delta T
Intrinsic capacity
mass in g

Question 7

Heat exchange equation

Answer 7

q(sys) = -q(surr)

Question 8

Pressure-Volume Work

Answer 8

W = -PdeltaV in L*atm

Question 9

1 L*atm

Answer 9

101.3 J

Question 10

State functions

Answer 10

internal energy
pressure
volume
enthalpy

Question 11

Not state functions

Answer 11

work

heat

Question 12

Bomb calorimeter: constant volume => all E evolved as heat

Answer 12

q(cal)= C(cal) x delta T
q(cal) = - q(rxn)

Question 13

Enthalpy (H): heat exchanged under constant pressure

Answer 13

H = E + PV

delta H = delta E + P(delta V) =q(p) constant p

Question 14

Coffee cup calorimeter: under constant pressure

q(rxn) = delta H (rxn)

Answer 14

q(soln) = m (soln) x Cs (soln) x delta T
q(rxn) = - q(soln)

Question 15

Standard state

1. gas
2. liquid/solid
3. solution

Answer 15

1. pure gas at 1 atm
2. pure substance in most stable form at 1 atm and usually 25 degrees C
3. 1 M