C2b Topic 4 - Groups in the Periodic Table

Question 1

Typical properties of metals

Answer 1

1) They conduct electricity well. This makes them great for making electrical wires.
2) They’re malleable - they can be bent and hammered into different shapes. This makes them great for making things like bridges and car bodies.

Question 2

Properties of transition metals

Answer 2

1) High melting points
2) Form very colourful compounds
3) They also have all the typical properties of metals

Question 3

Structure of metals that gives them their properties

Answer 3

1) Metals consist of a regular arrangement of atoms held together with metallic bonds.
2) The metallic bonds give the metal a giant structure consisting of positive ions and free electrons. This is because metallic bonds allow the outer electron(s) of each atom to become delocalised (move freely).
3) This creates a “sea” of delocalised electrons throughout the metal, which is what gives rise to many of the properties of metals. For example, the ability of electrons to move freely through the structure makes metals good conductors of electricity.
4) The giant metallic structure and strong bonds mean that metals have extremely high melting and boiling points and are insoluble.
5) They also allow layers of atoms to slide over each other, allowing metals to be bent and shaped. This makes metals malleable.

Question 4

The alkali metals are soft and have

Answer 4

Low melting points

Question 5

Group 1 elements react vigorously in

Answer 5

Water to form hydroxides.

Question 6

When alkali metals react in water this reaction makes an

Answer 6

Alkaline solution (which would change universal indicator to blue or purple)

Question 7

Metals are on the

Answer 7

Left and middle of the periodic table

Question 8

As you go down group 1..

Answer 8

The lone electron is in a shell that’s further way from the nucleus. As they are further apart, the attraction between the positively charged nucleus and the negatively charged electron decreases. This means the electron is easier to get rid of.

Question 9

Elements further down group 1 are _______ reactive

Answer 9

More!

Question 10

Lithium takes longer than sodium or potassium to react, so it’s the least reactive. Potassium takes the shortest time to react of these three elements so it’s the ________ reactive

Answer 10

Most!

Question 11

The elements in group 1 get more reactive as atomic number __________

Answer 11

Increases!

Question 12

The reaction of an alkali metal with water produces

Answer 12

Hydrogen. A lighted splint will indicate the hydrogen by making the notorious “squeaky pop” as the hydrogen ignites.

Question 13

Group 7 elements are known as the

Answer 13

Halogens!

Question 14

At room temperature:
Chlorine is….
Bromine is…
Iodine is…

Answer 14

Chlorine is… a fairly reactive, poisonous, dense green gas.
Bromine is… a dense, poisonous, orange liquid.
Iodine is…a dark grey crystalline solid.

Question 15

Halogens react with most metals to form

Answer 15

Metal halides!

Question 16

Halogens can react with hydrogen to form

Answer 16

Hydrogen halides

Question 17

Hydrogen halides are

Answer 17

Soluble! They dissolve in water to form acidic solutions.

Question 18

More reactive halogens will displace less reactive ones

Answer 18

1) The higher up Group 7, the more reactive an element is. This is because the outer shell is nearer to the nucleus, so the pull from the positive nucleus is greater which attracts extra electrons more strongly.
2) When halides dissolve in water, the halide ions are free to react.
3) If a more reactive halogen reacts with a solution containing halide ions it will displace the less reactive halogen. This is a displacement reaction.
4) E.g. Chlorine is more reactive than iodine (it’s higher up group 7). Chlorine therefore reacts with potassium iodine to form potassium chloride and iodine.

Question 19

Group 0 elements (the noble gases) are all

Answer 19

Inert, colourless gases

Question 20

Uses of argon

Answer 20

1) Provides inert atmosphere in filament lamps. As argon is non-flammable it stops the very hot filament from burning away.
2) It can also be used to protect metals that are being welded. The inert atmosphere stops the hot metal reacting with oxygen.

Question 21

Uses of helium

Answer 21

1) Airships
2) Party balloons
Helium has a lower density than air - it makes balloons float.