Defenitions I Might Actually Need

Question 1

Anhydrous

Answer 1

Containing no water molecules

Question 2

Hydrated

Answer 2

A crystalline compound containing water molecules

Question 3

Water of crystallisation

Answer 3

Water molecules that are bonded into a crystalline structure of a compound

Question 4

Volatility

Answer 4

The ease at which a liquid turns into a gas

Question 5

Polar covalent bonds

Answer 5

A bond with a permanent dipole, having + and - partial charges on the bonded atoms

Question 6

Permanent dipole

Answer 6

A small charge difference that does not change across a bond

Question 7

First ionisation energy

Answer 7

The energy required to remove one electron from each atom in one mole of gaseous atoms of an element to form one more of gaseous 1+ ions

Question 8

Enthalpy change of neutralisation

Answer 8

The enthalpy change when solutions of an acid and an alkali react together under standard conditions to produce 1 mole of water.

Question 9

Activation energy

Answer 9

The minimum energy required to start a reaction by the breaking of bonds

Question 10

Homogenous catalyst

Answer 10

A catalyst with the same physical state as the reactants

Question 11

Homologous series

Answer 11

A series of organic compounds with the same functional group but with each successive member differing by CH2

Question 12

Stereoisomers

Answer 12

Compounds with the same structural formula but a different arrangement of atoms in space

Question 13

Structural isomer

Answer 13

Molecules with the same molecular formula but a different structural formula

Question 14

E/Z isomerism

Answer 14

A type of stereoisomerism where different groups attached to each carbon of a C=C may be arranged differently in space, due to the restrictive rotation of the C=C

Question 15

Electrophile

Answer 15

An electron pair acceptor

Question 16

Nuclelophile

Answer 16

An electron pair donator

Question 17

Solid structures of simple molecular lattices

Answer 17

Covalently bonded molecules attracted by intermolecular forces, eg. Ice and I2

Question 18

Across a period, small decreases from eg. Be-B and from eg. N-O. Because,

Answer 18

Be-B - electron removed from a higher sub shell (p) which has more energy and so less energy is needed to remove the electron
N-O - first paired electron to be removed so because of repulsion less energy is needed

Question 19

Orbital

Answer 19

A region around the nucleus that can hold up to 2 electrons with opposite spins

Question 20

Strongest permenant dipole=

Answer 20

Biggest difference in electronegativity

Question 21

What is Ca(OH)2 used for?

Answer 21

In agriculture to neutralise acid soils

Question 22

What are Mg(OH)2 and CaCO3 used for?

Answer 22

Antacids in treating indigestion

Question 23

In S8…

Answer 23

Simple covalent molecules form a lattice

Question 24

Name the order of the qualitative tests

Answer 24

Carbonate
Sulphate
Halide

Question 25

What acid should be used for the carbonate test?

Answer 25

HNO3

Question 26

What should be used for the surface test?

Answer 26

Ba(NO3)2

Question 27

Standard conditions

Answer 27

298K 100KPa 1mol/dm3

Question 28

In a dynamic equilibrium:

Answer 28

- rate of forward = rate of backward | - Conc. Stays constant

Question 29

Le chateliers principal

Answer 29

When a system is in equilibrium and subjected to an external change, the system readjusts itself to counter the change

Question 30

If Kc = 1

Answer 30

Equilibrium halfway between

Question 31

Kc > 1

Answer 31

Equilibrium towards products

Question 32

Kc

Answer 32

Equilibrium towards reactants

Question 33

What does a Curley arrow show?

Answer 33

Movement of an electron pair

Question 34

Pi bond

Answer 34

Sideways overlap of adjacent p-orbitals above and below the bonding C atoms

Question 35

Sigma bond

Answer 35

Overlap of orbitals end to end directly between the bonding atoms

Question 36

Why are alkalis unreactive?

Answer 36

- strong sigma bonds - C-C bonds also non-polar - High bond enthalpy

Question 37

Why are alkenes more reactive than alkanes?

Answer 37

- Low bond enthalpy of pi bond (see wall)

Question 38

Why burn polymers?

Answer 38

To create steam to power a turbine

Question 39

Why use organic feedstock recycling?

Answer 39

As it is can reclaim monomers, gases and oils from waste polymers. These new raw materials can be re-used to create new polymers

Question 40

Why and how do you recycle PVC?

Answer 40

As it creates HCl when burnt, a corrosive gas. | You recycle by using solvents to dissolve the polymer (PVC)

Question 41

Benefits to the Env. Of photodegradable polymers

Answer 41

- Break down when absorb sun, energy not needed to recycle it

Question 42

Benefits to the Env. Of photodegradable polymers

Answer 42

- Used in bin liners so waste food and bags can be composted together - Leaves no toxic or visual residue when it breaks down

Question 43

Why the low volatility in alcohols compared to alkanes?

Answer 43

Higher B.P = Lower Volatility, | So alcohols have a higher boiling point because of strong hydrogen bondin

Question 44

Polarity in alcohols?

Answer 44

Alcohols are polar, because of the polar O-H bond (difference in electronegativity).

Question 45

How is the HBr for alcohol to haloalkanes formed?

Answer 45

NaBr + H2SO4 ----> NaHSO4 + HBr

Question 46

What is Cl radical in ozone reactions?

Answer 46

Catalyst

Question 47

How are halogen radicals produced in the atmosphere?

Answer 47

Action of UV radiation on CFCs in the atmosphere

Question 48

Pros of CFCs?

Answer 48

Refrigerants - low BP, unreactive | Propellant - low toxicity, no risk of fire

Question 49

What does infrared radiation cause covalent bonds to do?

Answer 49

They vibrate more and absorb energy

Question 50

How can IR spectroscopy be used in the modern world?

Answer 50

- Monitor gases causing air pollution, eg. CO and NO from car exhausts - In modern breathalysers to measure ethanol in the breadth