Groups in the Periodic table

Question 1

alkali metals

Answer 1

• They are all soft metals which can easily be cut with a knife
• They have relatively low densities and low melting points
• They are very reactive (they only need to lose one electron to become highly stable)

Question 2

As you go down group 1 …

Answer 2

• the number of shells of electrons increases by 1
• This means that the outermost electron gets further away from the nucleus, so there are weaker forces of attraction between the outermost electron and the nucleus
• Less energy is required to overcome the force of attraction as it gets weaker, so the outer electron is lost more easily
• So, the alkali metals get more reactive as you descend the group

Question 3

What are halogens?

Answer 3

Elements that are non-metals and poisonous

Halogens include fluorine, chlorine, bromine, iodine, and astatine.

Question 4

How many electrons do halogens have in their outermost shell?

Answer 4

Seven electrons

This electron configuration contributes to their similar chemical reactivity.

Question 5

What does it mean for halogens to be diatomic?

Answer 5

They form molecules made of pairs of atoms sharing electrons

This results in a single covalent bond between two halogen atoms.

Question 6

What type of bond do halogen atoms form with each other?

Answer 6

Single covalent bond

This bond occurs when two halogen atoms share a pair of electrons.

Question 7

How do the colours of halogens change?

Answer 7

they get darker as you go down the group

Question 8

chlorine test

Answer 8

damp blue litmus paper will be bleached white

Question 9

Properties of Noble Gases

Answer 9

all non-metal, monatomic (exist as single atoms), colourless, non-flammable gases at room temperature
The group 0 elements all have full outer shells of electrons; this electronic configuration is extremely stable
Elements participate in reactions to complete their outer shells by losing, gaining, or sharing electrons

Question 10

Noble Gases uses

Answer 10

• Helium is used for filling balloons and weather balloons as it is less dense than air and does not burn.
• Neon, argon and xenon are used in advertising signs
• Argon is used to provide an inert atmosphere for welding and to fill electric light bulbs
• Apart from older style incandescent light bulbs, argon is used in low energy light bulbs.