Groups in the periodic table

Question 1

Group 1 metals are known as what?

Answer 1

The Alkali metals.

Question 2

What are the alkali metals?

Answer 2

Lithium, sodium, potassium rubidium, caesium and francium.

Question 3

How many outer electrons do the alkali metals have?

Answer 3

1.

Question 4

What are the properties of alkali metals?

Answer 4

• Very soft

- Low melting points and boiling points

Question 5

What compounds do alkali metals form and why?

Answer 5

Ionic because they lose their outer electron so easily that sharing it to form a covalent is out of the question.

Question 6

Complete the sentence: the more readily a metal loses its outer electrons…

Answer 6

The more reactive it is.

Question 7

How does lithium react with cold water?

Answer 7

Lithium will move around the surface, fizzing furiously.

Question 8

How do sodium and potassium react with cold water?

Answer 8

They will move around the surface, fizzing, and melt in the heat of the reaction. Potassium even gets hot enough to ignite the hydrogen gas produced.

Question 9

What are the products of reacting alkali metals with water?

Answer 9

Hydroxide and hydrogen gas.

Question 10

What is the reactivity trend in Group 1?

Answer 10

The elements get more reactive as you go down the group because the outer electron is lost more easily as it becomes further away from the nucleus as you go down.

Question 11

Group 7 elements are known as what?

Answer 11

The Halogens.

Question 12

The group 7 elements have how many electrons in there outer shell?

Answer 12

7.

Question 13

What is a diatomic molecule?

Answer 13

They share one pair of electrons in a covalent bond, giving both atoms a full outer shell. e.g. Cl₂, Br₂, I₂.

Question 14

What does chlorine look like at room temperature?

Answer 14

A green gas.

Question 15

What does bromine look like at room temperature?

Answer 15

Red-brown liquid, which gives off an orange vapour.

Question 16

What does iodine look like at room temperature?

Answer 16

A dark grey crystalline solid, which gives off a purple vapour.

Question 17

What happens to the melting/boiling points as you go down Group 7?

Answer 17

As you go down Group 7 the melting points and boiling points of the halogens increase.

Question 18

What is the chemical test for chlorine?

Answer 18

Hold a piece of damp blue litmus paper over it. Chlorine will bleach the litmus paper, turning it white. It may turn red for a moment, that’s because chlorine is acidic.

Question 19

What is the reactivity trend for halogens?

Answer 19

The reactivity goes decreases as you go down the Group as the outer electron becomes harder to attract to fill the outer shell because it is further away from the nucleus.

Question 20

Halogens can react with hydrogen to form what?

Answer 20

Hydrogen halides, which are soluble and form acidic solutions.

Question 21

Halogens react with metals to form salts called what?

Answer 21

Metal halides.

Question 22

What is a displacement reaction?

Answer 22

This is where a more reactive element `pushes out’ (displaces) a less reactive element from a compound.

Question 23

The halogen displacement reactions are called what and why?

Answer 23

Redox reactions: The halogens gain electrons (reduction) whilst halide ions lose electrons (oxidation).

Question 24

In a redox reaction, which substance is reduced?

Answer 24

Halogens.

Question 25

In a redox reaction, which substance is oxidised

Answer 25

Halide ions.

Question 26

How can you use displacement reactions to find the reactivity trend?

Answer 26

• Start with a small amount of halide salt solution in a test tube
• Add a few drops of a halogen solution, shake tube
• If there is a colour change, then a reaction has happened. The halogens has displaced the halide ions from the salt.
• If there is no colour change then there has been no reaction. The halogen is less reactive then the halide and so can’t displace it

Question 27

Group 0 elements are called what?

Answer 27

The noble gases.

Question 28

Group 0 is made up of what elements?

Answer 28

Helium, neon, argon, krypton, xenon and radon.

Question 29

What are Group 0 elements at room temperature?

Answer 29

Colourless.

Question 30

What does monatomic mean?

Answer 30

Made up of single atoms.

Question 31

What does inert mean?

Answer 31

They don’t react.

Question 32

Why are the Group 0 elements inert?

Answer 32

They have a full outer shell.

Question 33

What are the uses of the noble gases?

Answer 33

• Provide an inert atmosphere
• Can be used in welding as it stops hot metals reacting with oxygen
• Helium is used in balloons as it has a lower density than air, so it can float

Question 34

What happens to the boiling point, melting point and density of the Group 0 elements as you go down the group?

Answer 34

They all increase.