Topic 4- Lecture 16

Question 1

Calorimeter

Answer 1

Device used to determine the amount of heat transfer

Question 2

Heat flow can’t be measured…

Answer 2

Directly

Measure temp before and after and flip sign

Question 3

Specific heat

Answer 3

Amount of heat it takes to raise the temp of 1 g of a substance by 1 K

Question 4

Heat lost or gained by a substance

Equation

Answer 4

Δq= m c ΔT
Heat lost or gained by a substance
Mass of substance
Specific heat capacity
Change in temperature

Question 5

Δq of reaction

ΔH of reaction

Answer 5

Heat lost or gained in the experiment

Heat lost or gained in the balanced chemical equation

Question 6

Hess’s law

Answer 6

Overall change in Enthalpy will be equal to the sum of the Enthalpy changes for the individual steps
Rearrange equations and flip signs of ΔH as necessary, add sums

Question 7

Standard Enthalpy of formation

Answer 7

Hypothetical value that indicates how much heat would be lost or gained during the formation of one mole of a substance
ΔH°f
°= standard state (298 K, 25°C)
Look values up in table

Question 8

ΔHrxn= ΣnΔH°f(products) - ΣnΔH°f (reactants)

Answer 8

Sum of
Stoichiometric coefficients
Look up in table

Question 9

Calorimetry

Answer 9

Lab technique

Measurement of heat transfer