Elements Of Life (EL)

Question 1

mass number

Answer 1

atomic number + no. neutrons

Question 2

isotope

Answer 2

atoms of the same element but different mass number

Question 3

relative atomic mass

Answer 3

average of the relative isotopic masses

Question 4

mass spectrometry

Answer 4

measures the atomic or molecular mass of particles sample and the relative abundance of different isotopes in an element

Question 5

nuclear fusion

Answer 5

two light atomic nuclei fuse together forming single heavier nucleus of new element and releasing energy

Question 6

spectroscopy

Answer 6

study of how light and matter interact

Question 7

wavelength =

Answer 7

speed of light / frequency

Question 8

particle theory of light

Answer 8

light is a stream of tiny packets of energy called photons

Question 9

energy of photon =

Answer 9

planck constant x frequency

Question 10

Bohr’s theory main points

Answer 10

electron in hydrogen atom exists only in certain definite energy levels, a photon of light is emitted/absorbed when electron changes energy level, energy of photon is equal to difference between two energy levels

Question 11

describe n=1 to n=4 shells

Answer 11

n=1 2 electrons
n=2 8 electrons
n=3 18 electrons
n=4 32 electrons

Question 12

describe the sub shells

Answer 12

s=2
p=6
d=10
f=14

Question 13

atomic orbitals

Answer 13

sub shells are divided into orbitals
s = 1 s orbital
p = 3 p orbitals
d = 5 d orbitals
f = 7 f orbitals

Question 14

periodicity

Answer 14

patterns or trends in physical properties within groups

Question 15

dative covalent bond

Answer 15

both bonding electrons come from the same atom

Question 16

bond angle for 4 single covalent bonds

Answer 16

109.5

Question 17

bond angle for 3 single covalent bonds + lone pair of electrons

Answer 17

107

Question 18

bond angle for 2 single covalent bonds + 2 lone pairs of electrons

Answer 18

104.5

Question 19

linear bond angle

Answer 19

180

Question 20

planar bond angle

Answer 20

120 (three groups of electrons)

Question 21

bipyramidal bond angles

Answer 21

120 to 90 depending on position in molecule (5 groups of electrons)

Question 22

relative atomic mass

Answer 22

mass of the atom relative to carbon-12, no units

Question 23

molar mass

Answer 23

mass of one mole

Question 24

amount in moles (n) =

Answer 24

mass (m) / molar mass (M)

Question 25

relative formula mass

Answer 25

sum of the relative atomic masses of the elements making it up

Question 26

Avogadro constant

Answer 26

6.02x10(23) mol. number of formula unitise one mole of a substance.

Question 27

Difference between molecular and empirical formula

Answer 27

molecular - actual numbers of different types of atom empirical - simplest ratio for the moles of atoms

Question 28

percentage yield =

Answer 28

(experimental yield / theoretical yield) x 100

Question 29

first ionisation enthalpy

Answer 29

energy required to pull an electron out of an atom X -> X+ +e-

Question 30

explaining change in thermal stability as group goes down group 1+2

Answer 30

cations with higher charge density can polarise negative charge cloud around the carbonate ion making it less stable and easier to break up on heating

Question 31

alkali

Answer 31

base that dissolves in water to produce HO- ions

Question 32

concentration in (mol/dm3) =

Answer 32

concentration (g/dm3) / molar mass (g/mol)