Topic 6 - Groups in the Periodic Table Flashcards
Group 1 metals are known as
Alkali metals
Group 7 elements are known as
Halogens
Group 0 elements are known as
Noble gases
Alkali metals properties
Low melting points and boiling points
Very soft
All Alkali metals top to bottom
Lithium, sodium, potassium, rubidium, caesium, francium
When alkali metals react with water
They react vigorously and produce hydrogen gas and a hydroxide of the metal
Lithium reaction with water
Moves around surface of water, and fizzes strongly
Sodium reaction with water
Move around surface and fizzes, melts in the heat of reaction
Potassium reaction with water
Moves around surface and fizzes. Melts in heat of reaction and ignites the hydrogen gas produced
The alkali metals get more reactive as you
Go down
Alkali metals are very reactive because
They readily lose their single outer electron to form an cation
Alkali metals get more reactvie going down because
The outer electron is further out, so has less attraction to the nucleus. therefore it can be lost more easily
All halogens top to bottoms
Flourine
Chlorine
Bromine
Iodine
Astatine
Chlorine at room temperature
Fairly reactive, poisonous green gas
Bromine at room temp
A poisonous, red-brown liquid which gives off orange vapour at room temp
Iodine at room temp
Dark grey crystaline solid which gives off purple vapour when heated
Physical properties of chlorine, bromine and iodine allow us to
Predict the properties of halogens as you carry on going down.
They get higher melting point, and they get darker
Chemical test for chlorine gas
Hold a piece of damp blue litmus paper over it. Chlorine will bleach the paper and turn it white
Halogen reactivity increases as you go
Up the group
Halogen react with some metals
vigorously and produce salts called metal halides
Halogens higher up in the group are more reactive because
They have less shells so can attract another electron more easily
Halogens react with hydrogen to
Make hydrogen halides
Hydrogen halides are
Soluble and dissolve in water to form acidic solutions
Halogen displacement reactions are
Redox reactions
A redox reaction is where
reduction and oxidation are occuring
During halogen displacement reactions
Halogen gain electrons(reduction)
Halide ions lose electrons(oxidation)
Noble gases properties
Inert, colourless gases
Monatomic(Not in molecules)
Full outer shells
Non-flammable
All noble gases top to bottom
Helium
Neon
Argon
Krypton
Xenon
Radon
Argon is used for
Filament bulbs to prevent the light burning
Helium can be used for
An inert atmosphere when metals are welded to prevent reaction with oxygen
Party balloons because it has alower density than air, so floats
How properties change as you go down group 0
Boiling and melting point, density increase