Enthalpys

Question 1

What is enthalpy of formation

Answer 1

Energy chage when forming one mole a substance using its element constituants

E.g C + O2 –> CO2

Question 2

What are the standard conditions

Answer 2

298K (25C)
100KPa
1 mol/dm3

Question 3

What is Hess Law

Answer 3

using enthalpy of formations to find enthalpy of reaction

Question 4

If using combustion which way to arrows do in Hess law

Answer 4

DOWN to HELLLLL (Fire)

Question 5

Definition of enthalpy of neutralisation

Answer 5

Energy change when an acid and base react forming one mole of H2O

Question 6

When should you round an answer

Answer 6

ONLY AT THE END OF THE QUESTION

Question 7

When doing bond enthalpy how do u do the final calc

Answer 7

React - Produc

Question 8

Limitations of bond enthalpys

Answer 8

Its the average of the bond in different chemical enviroments not that specific bond so not exact

Question 9

Definition of enthalpy of combustion

Answer 9

Energy needed to completely react one mole of something with O2

Question 10

How to convert C to K

Answer 10

+273 on

Question 11

Unit for Enthalpys?

Answer 11

KJ/Mol

Question 12

Definition of atomisation enthalpy

Answer 12

Energy to make a gas from element constituents

Question 13

Definition of Electron affiity

Answer 13

energy to add an electron to a gas

Question 14

definition of ionisation energy

Answer 14

remove one elctron from each atom in a mole of a gas

Question 15

equation for 2nd ionisation energy of o2

Answer 15

O+ (g) –> O2+(g) + e-

Question 16

Factors affecting first ionisation energy

Answer 16

Radius
Shielding
Nuclear charge