Topic 1-Atomic Structure

Question 1

What is the relative mass & charge of a proton?

Answer 1

Mass-1
Charge-1+

Question 2

What is the relative mass and charge of a neutron?

Answer 2

Mass-1
Charge-0

Question 3

What is the relative mass and charge of an electron?

Answer 3

Mass- 0.0005
Charge- 1-

Question 4

What is an isotope?

Answer 4

Isotopes of elements are atoms with the same number of protons & electrons but different numbers of neutrons.

Question 5

How can you identify an isotope?

Answer 5

Different mass numbers and amount of neutrons

Question 6

How do you calculate the relative atomic mass?

Answer 6

Relative mass= (relative isotopic mass x relative isotopic abundance)+ (relative isotopic mass 2 x relative isotopic abundance 2) / 100

Question 7

Define relative mass

Answer 7

The mean mass of an atom compared to 1/12th of the mass of an atom of carbon 12.

Question 8

Define relative isotopic mass

Answer 8

The mass of an atom of an isotope, compared to the mass of an atom of carbon 12.

Question 9

What does the y axis represent in mass spectrometry?

Answer 9

The abundance of ions, as a percentage

Question 10

What does the x axis of a mass spectrometry graph show?

Answer 10

The m/z value (mass/ charge ratio)

(Use it as the relative isotopic mass value)

Question 11

Name the number of orbitals, & how many electrons can be held in each sub shell

Answer 11

S- 1 orbital & 2 electrons
P- 3 orbitals & 6 electrons
D- 5 orbitals & 10 electrons
F- 7 orbitals & 14 electrons

Question 12

What groups are the s-block elements?

Answer 12

Groups 1 & 2

Question 13

What groups are the p-block elements?

Answer 13

Groups 3-7

Question 14

What groups are the d-block elements?

Answer 14

The metals in the centre of the periodic table

Question 15

In an atoms base state what energy level do they have their electrons at?

Answer 15

The lowest possible

Question 16

If what condition is met electrons move to a higher energy level?

Answer 16

Energy is absorbed

Question 17

As atoms absorb energy what happens to the separation distance between electrons and the nucleus?

Answer 17

Increases as they have more energy to overcome the electrostatic forces of attraction

Question 18

What causes electrons of an atom to drop to a lower/ their original energy level?

Answer 18

Energy is emitted/ released

Question 19

What shows the frequencies of light that are emitted when the electrons drop an energy level?

Answer 19

A line spectrum/ an emission spectrum. (The colours appear as lines on a dark background)

Question 20

Why are each elements emission spectra’s unique?

Answer 20

Each element has a unique structure & electron arrangement-> unique amounts of energy released as the electron drops down an energy level- unique emission spectra.

Question 21

Are energy levels discrete or continuous?

Answer 21

They’re discrete as all the energy levels have a fixed value.

Question 22

Define first ionisation energy

Answer 22

The energy required to remove 1 electron from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions.

Question 23

What is shielding?

Answer 23

As the number of electrons between the outer electrons and the nucleus increases, the outer electrons feel less attraction towards the nuclear charge. This lessening of the pull of the nucleus by the inner shell of electrons is called shielding.

More repulsion by other electrons- more effect as weaker attraction to the nuclear charge

Question 24

What does a high ionisation energy mean?

Answer 24

There’s strong attraction between the electron and the nucleus.

More energy is needed to overcome the attraction and remove the electron.

Question 25

Factors affecting ionisation energy?

Answer 25

Atomic radius
Nuclear charge

Question 26

What are the trends in ionisation energy across the periodic table?

Answer 26

Decreases down a group (same charge but larger atomic radii-> less attraction as shells get further from the nucleus- less energy required)

Increases (left to right) across a period- greater nuclear charge & the atomic radius decreases across a period

Question 27

When did Mendeleev create the periodic table?

Answer 27

1869

Question 28

Do we still use Mendeleev’s period table model?

Answer 28

No, we order elements based on atomic number now, & other changes.

Question 29

List the order of electron sub shells

Answer 29

1S 2S 2P 3S 3P 4S 3D 4P 5S 5P 6S 4F 5D 6P 7S 5F 6D 7P

Question 30

Why does atomic radius decrease across a period?

Answer 30

As the number of protons/ nuclear charge increases, the electrostatic forces of attraction between the nucleus and the outer electrons increases and so the atomic radius decreases as the atom is pulled closer inwards.

Question 31

Why dont the electrons added as you move across a period increase the atomic radius?

Answer 31

They’re located on the outermost energy level-> don’t influence the shielding, as it’s generally only the inner electrons that affect the strength of shielding.

Question 32

Which electrons affect the rate of shielding the greatest?

Answer 32

The innermost electrons

Question 33

Why is there a drop between groups 5 & 6 in terms of ionisation energy?

Answer 33

Elements with singly filled or full sub shells are more stable than those with partially filled sub shells, so have higher first ionisation energies.

Question 34

Why is there a drop in ionisation energies from period 2 to 3?

Answer 34

Whilst they have the same charge, they have more electrons, so theres a greater shielding effect