CH 6 VOCAB

Question 1

Exothermic

Answer 1

Energy goes from system to to the surroundings (heat given off)

Question 2

Endothermic

Answer 2

Energy required, going from surroundings to system (heat taken in, colder)

Question 3

Surroundings

Answer 3

Everything else

Question 4

System

Answer 4

Things causing change in energy

Question 5

Enthalpy Change

Answer 5

Sum of all energy content

Question 6

Enthalpy profile diagrams

Answer 6

Diagram that shows enthalpy changes of a substance

Question 7

Standard conditions

Answer 7

1 atm, 1 M concentrated solutions, pure substances
conditions that must be present to compare enthalpy changes

Question 8

Standard enthalpy change

Answer 8

enthalpy change under standard conditions (100kpa, 298k)

Question 9

SEC of reaction

Answer 9

enthalpy change when reactants react to make products under standard conditions and standard states

Question 10

SEC of formation

Answer 10

enthalpy change when one mol of compound is formed from its components under standard conditions, standard states

Question 11

SEC of combustion

Answer 11

enthalpy change when one mol of substance is burnt in excess oxygen under standard conditions, standard states

Question 12

SEC of neutralization

Answer 12

enthalpy change when one mol of water is formed by reaction of acid and alkali under standard conditions

Question 13

SEC of solution

Answer 13

enthalpy change when one mole of solute is dissolved in a solvent to form infinitely dilute solution under standard conditions

Question 14

SEC of atomization

Answer 14

enthalpy change when one mole of gaseous atoms form from its elements under standard conditions

Question 15

SEC of an anhydrous salt

Answer 15

enthalpy change when one mole of hydrated salt is formed from one mol of anhydrous salt under standard conditions

Question 16

Hess’s Law

Answer 16

total enthalpy change of a reaction is independent of how a reaction takes place

Question 17

Bond energy

Answer 17

energy needed to break 1 mole of a particular bond in 1 mol of gaseous molecules

Question 18

Average bond energy

Answer 18

general bond energy value used for a bond when the exact bond energy is not required. used because strength btwn to particular types of atoms are slightly different in different compounds

Question 19

Lattice energy

Answer 19

nrg needed to form an ionic compound from gaseous ions at standard conditions

Question 20

enthalpy change of atomization

Answer 20

nrg used when 1 mol of gaseous atoms are formed from its element under stp

Question 21

electron affinity

Answer 21

enthalpy change when 1 mol of electrons is added to 1 mol of gaseous atoms to form 1 mol of gaseous -1 ions under stp

Question 22

second electron affinity

Answer 22

enthalpy change when 1 mol of electrons are added to 1 mole gaseous 1- ions to form 1 mol gaseous -2 ions under stp

Question 23

born haber cycle

Answer 23

enthalpy cycle used to calculate lattice nrg

Question 24

ion polarization

Answer 24

when a small highly charged cation distorts the electron field of its opposing anion (charge density affected)

Question 25

polarizing power

Answer 25

strength/ability of a cation to distort an anion

Question 26

enthalpy change of solution

Answer 26

nrg released or absorbed when 1 mol of ionic solid dissolves in excess water to form a dilute solution

Question 27

enthalpy change of hydration

Answer 27

nrg change when 1 mol of specific gaseous ion dissolves in sufficient water to form a very dilute sltn