Groups in the periodic table Flashcards
What are group 1 metals known as
Alkali metals
What are the group 1 metals
Lithium, Sodium Potassium, Rubidium, Caesium, Francium
Physical properties of group 1 metals
Low meltimg and boiling points
Very soft (they can be cut with knife)
What do alkali metals form
ionic compound because they lose their electron as its really easy and they only have one electron on the outer shell
Why are group 1 metals very reactive?
They readily lose their single outer electron to form a 1+ ion with a stable electronic structure
The more readily a metal loses it’s outer electron, the more reactive it is - so the group 1 metals are very reactive
Why do the metals get more reactive as you go down the group ?
(group 1)
As you go down group 1, the alkali metals get more reactive. The outer electron is more easily lost because its futhre away from the nucleus (the atomic radius is larger) - so it’s less strongly attracted to the nuclues and less energy is needed to remove it
What are group 7 metals called
Halogens
Describe Fluorine
Gas - at room temperature
Yellow
Low melting and boiling points
Most reactive
Describe Chlorine
More reactive
Gas at room temperature
Green
Low melting and boiling point
Describe Bromine
Liquid at room temperature
Brown-red
What is the test for chlorine?
Hold a piece of damp blue litmus over it.
Chlorine will bleach the litmus paper, turning it white
It may also turn red for a moment first as the solution of chlorine is acidic
Describe iodine
Dark grey crystalline solid whicg gives off a purple vapour when heated
Describe astatine
Solid at room tempertature
Grey-black solid
What does diatomic molecules mean?
The halogens exist as diatomic molecules (e.g. Cl₂, Br₂)
Sharing one pair of electrons in a covalent bond giving both atoms a full outer shell
Does the melting point increase or decrease as you go down the group?
(group 7)
The melting point increases down the group therefor they become more solid as you go down
