Energetics

Question 1

Standard conditions

Answer 1

10lkpa
298k
1 moldm3 concentration fir all solutions

Question 2

Hesses law

Answer 2

The enthalpy change for a chemical reactant is the same no matter what route is taken

Question 3

Formation

Answer 3

Right - left

Question 4

Combustion

Answer 4

Left - right

Question 5

Mean bond enthalpy cal

Answer 5

Left - right

Question 6

Equations fur calorimetery

Answer 6

Q= mc ^ t
^H = Q/N

Question 7

2 moles

Answer 7

Use smallest moles
Use fatal volume

Question 8

Assumption made in calorimetery

Answer 8

Energy transferred = energy released

Question 9

Sources of error and improvement

Answer 9

1. Heat loss = add a lid / insulate
2. Incomplete combustion
3. Reduce distance between flame and beaker
4. Put sleeve around flame to protect it from draughts
5. Some fuel evaporates

Question 10

Use of cooling curve

Answer 10

Need polyesteene cup ,lid, thermometer , heat source
1. Record temperature for a 3 minutes until a accurate intitial stable temperature can be determined
2. Mix reactants
together then record temperature every 30csecs until trend I seen
3. Plot a graph for temperature v time
4. Extrapolate the cooling curve back to pound of addition to establish a theoretical temperature change for heat loss
Then use equations