definitions

Question 1

atomic number

Answer 1

no. of protons

Question 2

mass number

Answer 2

total no. of protons and neutrons

Question 3

isotopes

Answer 3

atoms with the same number of protons but a different number of neutrons

Question 4

TOF mass spectrometer

Answer 4

analytical instrument that gives accurate information about relative isotopic mass and relative abundance of isotopes

Question 5

electrospray ionisation?

Answer 5

high voltage applied to sample 
dissolved in a polar solvent 
molecules lose an electron
form gaseous 1+ ions
must be ionised so they can be accelerated towards negatively charged plate

Question 6

relative mass

Answer 6

the weighted mean mass of an atom of an element relative to 1/12 of the mass of one atom of carbon-12

Question 7

first ionisation energy

Answer 7

the energy required to remove an electron from each atom in one mole of gaseous atoms

Question 8

what is an acid?

Answer 8

a species that is a proton donor

Question 9

activation energy?

Answer 9

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

Question 10

addition polymer

Answer 10

the process in which unsaturated alkene molecules add on to a growing polymer chain one at a time to form a very long saturated molecule chain

Question 11

addition reaction

Answer 11

a reaction in which a reactant is added to an unsaturated molecule to make a saturated molecule

Question 12

adsorption

Answer 12

the process that occurs when a gas liquid or solid is held to the surface of a solid (RARELY A LIQUID)

Question 13

alkali?

Answer 13

a type of base that dissolves in water forming hydroxide ions

Question 14

alkanes?

Answer 14

the homologous series with the general formula cnH2n+2

Question 15

alkyl group?

Answer 15

an alkane with a hydrogen ion removed

alkyl groups are often shown as ‘R’

Question 16

what does anhydrous mean?

Answer 16

substance containing no water molecules

Question 17

what is an anion?

Answer 17

a negatively charged ion

Question 18

atom economy?

Answer 18

molecule mass of the desired product/sum of molecular masses of all products x 100

Question 19

atomic orbital?

Answer 19

a region within an atom that can hold up to two electrons with opposite spins

Question 20

average bond enthalpy?

Answer 20

the average enthalpy change that takes place when breaking, by homolytic fission, 1 mol of a given type of bond in the molecules of a gaseous substance

Question 21

avogadro constant?

Answer 21

6.022 x 10^23

Question 22

what is a base?

Answer 22

species that is a proton acceptor

Question 23

bond enthalpy

Answer 23

the enthalpy change that takes place when breaking, by homolytic fission, 1 mol of a given bond in the molecules of a gaseous species

Question 24

catalyst?

Answer 24

a substance that increases the rate of a chemical reaction without being used up

Question 25

cation?

Answer 25

positively charged ion

Question 26

cis - trans isomerism?

Answer 26

type of E/Z isomerism in which there is a non-hydrogen group and a hydrogen on each side of a C=C double bond: the cis isomer has the H atom of each carbon on the same side the trans has the H atom of each carbon on different sides

Question 27

concnetration?

Answer 27

amount of solute in solvent | mol per dm^2

Question 28

coordinate bond / dative covalent bond

Answer 28

a shared pair of electrons which has only been provided by one of the bonding atoms

Question 29

covalent bond?

Answer 29

bond formed by a shared pair of electrons

Question 30

what is cracking?

Answer 30

the breakdown of long-chained saturated hydrocarbons to form a mixture of shorter-chained alkanes and alkenes

Question 31

what is dehydration?

Answer 31

an elimination reaction in which water is removed from a saturated molecule to make an unsaturated molecule