The Periodic Table

Question 1

Who was the greatest contributor to the development of the periodic table?

Answer 1

The Russian scientist Mendeleev

Question 2

How did Mendeleev arrange the elements?

What was written on each card?

Answer 2

Columns in order of atomic weight.

The symbol of the element and its atomic weight.

Question 3

What was Mendeleev’s stroke of genius when he arranged the elements?

Answer 3

He left spaces for undiscovered elements. These were later filled as more elements were discovered.

Question 4

What is the name for group 0?

Answer 4

The noble gases.

Question 5

Why are the elements of group 0 so unreactive?

Answer 5

They have full outer shells.

Question 6

What are some uses for Noble gases?

Answer 6

Neon lights
Deep sea diving (helium mixed with oxygen)
Air ships

Question 7

Where are the transition metals located?

Answer 7

Middle of the periodic table

Question 8

What are the properties of the transition metals?

Answer 8

Hard
Shiny
Malleable

Question 9

What are some uses for transition metals?

Answer 9

Catalytic converters
Alloys used in coins
Clay glaze mixtures

Question 10

What is the name given to horizontal rows in the periodic table?

Answer 10

Periods.

Question 11

Where are the most reactive metals found?

Answer 11

Group 1.

Alkali metals.

Question 12

How do alkali metals react with water?

Answer 12

Metal floats, fizzes and releases heat. Eventually disappears in a smoke/crackle explosion.
Reactions become more violent as you go down the group.

Question 13

What is the name given to metals in group 2?

Answer 13

Alkaline earth metals

Question 14

What is the name given to group 7 elements?

Answer 14

Halogens.

Question 15

What are the formulae for all group 7 elements?

Answer 15

They’re all diatomic.
E.g. F2, Cl2 etc.

Question 16

How do group 7 elements change down the group?

Answer 16

Become bigger atoms

Become less soluble, though none are particularly soluble

Increasing melting/boiling points.

Become less reactive (atoms have more shells of electrons further down the group, so the outermost shell gets further away from the positive attraction of the nucleus, meaning the attraction between the nucleus and an electron from a different atom becomes weaker and so are less reactive).

Question 17

What does fluorine look like?

Answer 17

Pale yellow gas

Question 18

What does chlorine look like?

Answer 18

Pale green gas

Question 19

What does bromine look like?

Answer 19

Red-brown liquid

Question 20

What does iodine look like

Answer 20

Grey-black solid that gives a purple vapour
Yellow - Brown when mixed with water.

Question 21

What does astatine look like

Answer 21

Black radioactive solid.

Question 22

What is sublimation?
Give an example of a group 7 element that sublimes.

Answer 22

The process of an element changing from a solid to gaseous state without going through a liquid state.
Iodine.

Question 23

How do group 7 elements react with eachother?

Answer 23

Halogens are able to displace other less reactive halogens (ones below them) in a compound.

E.g.
Chlorine + potassium bromide -> potassium chloride + bromine
(Reactions like this would cause the solution to turn the colour of the displaced element, in this instance brown)

Question 24

How do the positively charged elements (groups 1-3) differ in terms of reactivity down the group than the negatively charged elements (groups 5-7)

Answer 24

Groups 1-3 become more reactive down the group as they have a small number of electrons in their outer shells that are more easily lost as go down the group as the distance between the nucleus and outer shell becomes greater and the electrons are less attracted to it.

Groups 5-7 become less reactive down the group as they have a large number of electrons in their outer shell that cannot be lost. The distance between the outer shells and nucleus becomes greater as you go down the group so the attraction between the nucleus and electrons from other atoms becomes weaker and they are less likely to react.