atomic structure and the periodic table

Question 1

what’s the mass and charge of the 3 subatomic particles?

Answer 1

proton charge = +1 / mass = 1

neutron charge = 0 / mass = 1

electron charge = -1 / mass = 0.0005 (1/2000)

Question 2

what’s an ion?

Answer 2

when an atom becomes charged one gaining or losing electrons

Question 3

a cation is…

Answer 3

a positively charged ion

Question 4

an anion is…

Answer 4

a negatively charged ion

Question 5

an isotope is…

Answer 5

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

Question 6

relative atomic mass (Ar) definition

Answer 6

The weighted mean mass of an atom of an element compared with one-twelfth of the mass of an atom of carbon-12.

Question 7

relative isotopic mass definition

Answer 7

The mass of an atom of an isotope compared to one-twelfth of the mass of an atom of carbon-12.

Question 8

Ar equation (mass spectrometry)

Answer 8

( (abundance A x m/z A) + (abundance B x m/z B) ) / 100

Question 9

how do you predict mass spectra? (4 steps)

Answer 9

1- write percentages as decimals
2- make a table of combinations of the isotopes (multiply abundances together)
3- any molecules that are the same, you add together
4- divide all values by the smallest value

Question 10

what does the M+1 / molecular ion peak tell you?

Answer 10

the relative molecular mass of the molecule

Question 11

S sub-shell
- no of orbitals
- no of electrons

Answer 11

1 orbital, 2 electrons

Question 12

P sub-shell
- no of orbitals
- no of electrons

Answer 12

• 3 orbitals
• 6 electrons

Question 13

D sub-shell
- no of orbitals
- no of electrons

Answer 13

• 5 orbitals
• 10 electrons

Question 14

F sub-shell
- no of orbitals
- no of electrons

Answer 14

• 7 orbitals
• 14 electrons

Question 15

s orbital shape

Answer 15

spherical

Question 16

p orbital shape

Answer 16

dumbbell

Question 17

what is spin pairing?

Answer 17

When 2 electrons occupy 1 orbital they ‘spin’ in opposite directions

Question 18

how are orbitals filled?

Answer 18

Filled singly in a sub-shell before pairing to avoid repulsion. Lower energy orbitals are filled first.

Question 19

s block

Answer 19

groups 1 and 2

Question 20

d block

Answer 20

transition metals

Question 21

p block

Answer 21

groups 3-8

Question 22

f block

Answer 22

lanthanide and actinide series

Question 23

emission spectra is evidence to prove…

Answer 23

the existence of quantum shells

Question 24

first ionisation energy is…

Answer 24

the energy required to remove the outer electron from one mole of gaseous atoms to produce 1 mole of gaseous ions each with a charge of 1+

Question 25

first ionization energy equation

Answer 25

X(g) -> X+(g) + e-

Question 26

shielding effect on ie

Answer 26

the reduction of the electrostatic attractive forces between a nucleus and its outer electrons due to the blocking effect of inner electrons, and added shells.
- less ie required

Question 27

nuclear charge effect on ie

Answer 27

the higher the number of protons in the nucleus, the higher the nuclear charge, and hence the stronger the electrostatic forces of attraction.
- higher ie required

Question 28

nuclear charge effect on ie

Answer 28

the higher the number of protons in the nucleus, the higher the nuclear charge, and hence the stronger the electrostatic forces of attraction.
- higher ie required

Question 29

atomic size effect on ie

Answer 29

the bigger the atom, the further the outer electron is from the nucleus.
the attractive forces between the nucleus and the outer electrons reduces.
this makes it easier to remove electrons.
less ie required

Question 30

1st IE trend down a group

Answer 30

• decreases
  because…
  atomic radii increases
  shielding increases
  …so electrostatic attraction decreases.

Question 31

successive ionization energy is…

Answer 31

Energy required to remove a second, third, fourth (etc.) electron from the same atom

Question 32

1st IE across a period

Answer 32

increases
this is because nuclear charge increases which increases the attraction between the nucleus and valence electron

Question 33

atomic radii across a period 3

Answer 33

decreases
increased nuclear charge which pulls the outer shell closer to the nucleus

Question 34

atomic radii across a period 3

Answer 34

decreases
increased nuclear charge which pulls the outer shell closer to the nucleus

Question 35

a decrease in IE at Al is evidence for…

Answer 35

atoms having sub shells. the outer electrons in aluminium sits in a higher energy sub-shell, slightly further from the nucleus than the outer electrons in magnesium

Question 36

a decrease in IE at Al is evidence for…

Answer 36

atoms having sub shells. the outer electrons in aluminium sits in a higher energy sub-shell, slightly further from the nucleus than the outer electrons in magnesium

Question 37

period 3 melting points

Answer 37

1st 3 elements- Na, Mg, Al. they have metallic bonding.

silicon has the highest mp, it has a giant covalent structure.

phosphorus has a lower mp due to a weaker simple molecular structure. mp is determined by weaker london forces.

sulfur is higher due to larger simple molecular structure and larger london forces.

chlorine and argon have smaller london forces and chlorine has a smaller simple molecular structure