Periodic Table

Question 1

What was John Newlands table called?

Answer 1

Law of octaves

Question 2

Who created the first modern periodic table?

Answer 2

Dmitrti Mendeleev

Question 3

Why did Mendeleevs table prove accurate?

Answer 3

He left gaps, which predicted undiscovered elements, and swapped order of some elements to fit the pattern
These undiscovered elements were predicted correct

Question 4

What three differences are there between Mendeleevs table and the modern periodic table?

Answer 4

• more elements and groups (transition metals) in modern table
• modern periodic table is in order of atomic mass, rather than Mendeleevs in order of atomic number
• there is no group 0 in Mendeleevs table

Question 5

What are the group 1 elements?

Answer 5

Commonly referred to as alkali metals

• lithium (Li)
• sodium (Na)
• potassium (K)
• rubidium (Rb)
• caesium (Cs)

Question 6

How hard are the group 1 metals?

Answer 6

They are very soft, with lithium requiring a sharp knife, and getting progressively easier to cut further down the group

Question 7

How dense are the group 1 metals?

Answer 7

Li, Na and K would float on water, Rb and Cs would sink
They get progressively denser going down the group

Question 8

How do the melting and boiling points of group 1 metals compare to other metals and why?

Answer 8

Much lower melting points, and the further you go down the group, the lower the mp, as +ve ions get bigger, so weaker attraction, and bonds are easier to break

Question 9

Why are group 1 metals kept in oil?

Answer 9

To prevent them from reacting with the air
They tarnish when exposed to air

Question 10

What occurs when group one metals react with water?

Answer 10

• they float
• they move about on surface
• effervescence
• flame on all except Li

Question 11

What substance is formed in this reaction and what is its pH?

Answer 11

Hydroxide (OH)
pH 13/14

Question 12

How does reactivity of group 1 metals change as you go down the group?

Answer 12

• atoms get bigger further down group
• outer electron further from nucleus
• attraction from nucleus is weaker, so it is more easily lost
• therefore metals are more reactive further down the group

Question 13

What features do all group 1 compounds have?

Answer 13

• all ionic
• all white
• all soluble in water
• all solutions are colourless

Question 14

Are group 7 atoms (halogens) diatomic?

Answer 14

Yes

Question 15

What Bond exists between halogen atoms in the pairs?

Answer 15

Covalent

Question 16

Why does mp of halogens get HIGHER as you go DOWN the group?

Answer 16

Halogens exist as diatonic molecules, so as you go down group, the bond between the atoms gets stronger as the atoms are larger, so intermolecular forces are stronger and need more heat energy to break

Question 17

What is formed when a halogen reacts with a metal, and what is this type of reaction called?

Answer 17

• a halide
• direct combination (the only product is the compound)

Question 18

How does reactivity change in halogens as you go UP the group?

Answer 18

It is easier to gain an electron when atom is smaller due to greater force of attraction from the nucleus, so higher up the group is more reactive

Question 19

How do you make ionic equations?

Answer 19

Separate equation into individual bits, and cancel out bits that are present on each side

Question 20

What is the acronym for half equations?

Answer 20

OIL RIG

Oxidation is loss
Reduction is gain

Question 21

How do you get an oxidation half equation from an ionic equation?

Answer 21

Work out the element that loses electrons, then wrote out just the bits of that element as an equation, and ‘- how many electrons it loses’ at the end

Question 22

How do you get an reduction half equation from an ionic equation?

Answer 22

Find the element that has gained electrons, then write out just those bits as an equation, and ‘+ how many electrons it gained’ before the ->

Question 23

What colour and state is fluorine at room temp?

Answer 23

Pale yellow
Gas

Question 24

What colour and state is chlorine at room temp?

Answer 24

Pale green
Gas

Question 25

What colour and state is bromine at room temp?

Answer 25

Brown
Liquid

Question 26

What colour and state is Iodine at room temp?

Answer 26

Dark grey
Solid

Question 27

What are the colours of group 7 vapours?

Answer 27

Fluorine: pale yellow
Chlorine: pale green
Bromine: red-brown
Iodine: purple

Question 28

What is the test for chlorine gas?

Answer 28

Chlorine turns damp blue litmus paper red, then bleaches it

Question 29

Why are noble gases/ group 8 unreactive?

Answer 29

They have a full outer shell of electrons

Question 30

What state and colour are noble gases at room temp?

Answer 30

Colourless gases

Question 31

How do boiling points and densities change going DOWN the group?

Answer 31

Higher boiling points and densities further down the group

Question 32

Guys this is scary why can they have 18 electrons on an outer shell 😰

Answer 32

Scary stuff right

Question 33

What are uses for noble gases?

Answer 33

Neon lamps
Airships
Breathing apparatus for diving
Welding
Sunbeds
Lasers
Fog lights
Strobes
Radiotherapy

Question 34

What properties do transition metals have?

Answer 34

• most typical metal properties
• much less reactive
• good catalysts
• can form more than one type of ion
• form coloured compounds