Inorganic and Physical Chemistry

Question 1

What is the unit for the energy in one mole of photons

Answer 1

kJ mol^-1

Question 2

What is the unit for the energy of a photon

Answer 2

Joules (J)

Question 3

What equation gives the energy in one mole of photons

Answer 3

E=Lhf/1000

Question 4

How is atomic emission spectra produced

Answer 4

An electron drops from a higher to a lower energy level, releasing a quantised amount of energy in the form of a photon.

Question 5

How is atomic absorption spectra produced

Answer 5

A photon is incident on an atom and it’s energy promotes an electron from a lower to a higher energy level.

Question 6

How many electrons can an atomic orbital hold

Answer 6

2

Question 7

The four quantum numbers and their symbols are

Answer 7

principal (n), angular momentum (l), magnetic (m) and spin (s)

Question 8

subshells that have the same energy are called

Answer 8

degenerate

Question 9

aufbau principle

Answer 9

electrons fill orbitals in order of increasing energy

Question 10

pauli exclusion principle

Answer 10

no two electrons in an atom have the same four quantum numbers

Question 11

hund’s rule

Answer 11

when degenerate orbitals are available, electrons fill each orbital singly and with parallel spin before pairing up to fill the orbitals

Question 12

2 electron pairs, shape and angles

Answer 12

linear, 180°

Question 13

3 electron pairs shape and angles

Answer 13

trigonal planar, 120°

Question 14

4 electron pairs shape and angles

Answer 14

tetrahedral, 109.5°

Question 15

5 electron pairs shape and angles

Answer 15

trigonal bipyramidal, 120° and 90°

Question 16

6 electron pairs shape and angles

Answer 16

octahedral, 90°

Question 17

why is water bent and not linear

Answer 17

the non-bonding pairs of electrons create a greater repulsion, reducing the bond angles between the hydrogens

Question 18

why don’t copper and chromium follow the aufbau principle

Answer 18

an electron from the 4s subshell is promoted to form a more stable half filled or full 3d subshell

Question 19

oxidation

Answer 19

an increase in oxidation number

Question 20

reduction

Answer 20

a decrease in oxidation number

Question 21

transition metal complexes consist of

Answer 21

a central metal ion surrounded by ligands

Question 22

what are ligands

Answer 22

negative ions or uncharged molecules with one or more non-bonding pairs of electrons

Question 23

what are dative bonds

Answer 23

where both electrons in a bond are donated by one atom

Question 24

monodentate, bidentate, hexadentate ligands have

Answer 24

1, 2 and 6 pairs of non-bonding electrons respectively

Question 25

splitting of d orbitals

Answer 25

when ligands approach the metal ion along the x, y and z axes, the electrons that lie on the axes gain energy so the d orbitals are 'split' no longer degenerate

Question 26

splitting of d orbitals allows

Answer 26

transition metals to absorb light

Question 27

energy difference between 'split' d orbitals depends on

Answer 27

the position of the ligands in the electrochemical series

Question 28

heterogeneous catalysts

Answer 28

are in a different state to the reactants

Question 29

homogeneous catalysts

Answer 29

are in the same state to the reactants

Question 30

in a chemical equilibrium

Answer 30

the rate of the forward and reverse reaction are equal and the concentration of the products and reactants are constant

Question 31

equilibrium position is affected by

Answer 31

temperature, concentration of products or reactants and if there and different moles of gasses on both sides, pressure

Question 32

heterogeneous equilibrium

Answer 32

not all the species are in the same state

Question 33

homogeneous equilibrium

Answer 33

all the species are in the same state

Question 34

what affects the value of k

Answer 34

K is only affected by temperature

Question 35

affect of endothermic and exothermic reactions on equilibrium

Answer 35

endothermic favours products so K increases, exothermic favours reactants so K decreases

Question 36

amphoteric

Answer 36

substances that can act as both acids or bases

Question 37

strong acids

Answer 37

nitric acid, sulphuric acid and hydrochloric acid, dissociate fully (ionise) in water and the reaction is irreversible

Question 38

weak acids

Answer 38

carboxylic acids, carbonic acid and sulphurous acid, dissociate partially in water and the reaction is reversible

Question 39

monoprotic and diprotic acids

Answer 39

contain one and two hydrogen atoms per molecule respectively

Question 40

strong bases

Answer 40

oxides and hydroxided of the alkali metals and soluble oxides and hydroxides of the group 2 metals, dissociate fully (ionise) in water and the reaction is irreversible

Question 41

weak bases

Answer 41

amines, dissociate partially in water and the reaction is reversible

Question 42

neutral salts acidic salts alkaline salts

Answer 42

a strong acid and a strong base a strong acid and a weak base a strong base and a weak acid

Question 43

what are soaps

Answer 43

salts of fatty acids (weak acids) and strong bases

Question 44

acid

Answer 44

proton donor

Question 45

base

Answer 45

proton acceptor

Question 46

conjugate acid

Answer 46

the species left over when bases accept a proton

Question 47

conjugate base

Answer 47

the species left over when acids donate a proton

Question 48

buffer solution

Answer 48

a solution where the pH remains approximately constant when small amounts of acid, base or water are added

Question 49

acid buffer solution consists of

Answer 49

a weak acid and one of its salts

Question 50

basic buffer solution consists of

Answer 50

a weak base and one of its salts

Question 51

indicators

Answer 51

are used in acid-base titrations as they change colour at the end-point of the reaction. usually weak acids in which the colour of the acid varies from its conjugate base

Question 52

entropy

Answer 52

measure of the amount of disorder within a system

Question 53

feasible reactions

Answer 53

tend towards the products rather than the reactants, the total entropy must increase

Question 54

for a reaction to be feasible

Answer 54

the free energy change must be less than zero