Topic 6- Groups In The Periodic Table Flashcards
Group 1 metals are also known as the…
Alkali metals
The alkali metals physical properties?
- Low melting points and boiling points (compared to other metals)
- Very soft
Alkali metals have similar chemical properties because…
This also means that they form… but not…
Because they all have one outer electron
They do form ionic compounds (they loose the single electron) but don’t form covalent bonds
Group one metals are … reactive
Linked to electron configurations because…
Pattern of reactivity
Very reactive
Because there is only one electron on the outer shell which means that when metals react the outer electron is lost to make the atom stable (reactive)
The reactivity increase down the table because there are more shells to shield the electrostatic attraction reducing the pull (less attraction the further away from the nucleus) making it easier to loose the electron
When alkali metals are put in water they react…
The reaction produces…
Example…
React vigorously
Hydrogen gas and a hydroxide of the metal
Eg. Sodium + Water = Sodium hydroxide + Hydrogen
The reactivity with water ... down the table because... Lithium reaction? Sodium reaction? Potassium reaction? Rubidium and Caesium reaction?
Increase down the table because the outer electron gets lost more easily in the reaction
Lithium- move around the surface, fizzing furiously
Sodium- (same as lithium) and melt in the heat of the reaction
Lithium- (same as sodium) can get hot enough to ignite the hydrogen gas produced
Rubidium and Caesium- react violently and explode
Group 7 elements are also known as…
They have… chemical properties because…
The halogens
Similar chemical properties because they all have 7 electrons on the outer shell
As you go down group 7 the boiling points and melting points... This means that at room temperature: Chorine... Bromine... Iodine...
Increase
Chlorine… is a fairly reactive, poisonous, green gas
Bromine… is a poisonous, red-brown liquid, which gives off an orange vapour at room temperature
Iodine… is a dark grey crystalline solid which gives off a purple vapour when heated
To test for chlorine gas…
Use damp blue litmus paper over where the gas
Chlorine will bleach the paper turning it white
Reactivity… down group 7
Because…
Reactivity decreases
Because a halogen atom only needs to gain one electron to form a stable structure
The easier it is to attract an electron, the more reactive the halogen will be
So further down group 7 it’s harder to attract the extra electron because the outer shell is further away from the nucleus (weaker electrostatic attraction from the more shields)
The halogens will react vigorously with some metals to form…
Halogens also react with hydrogen to form…
Salts called metal halides
Hydrogen halides which are soluble and dissolve in water to form acidic solutions
The higher up in group 7, the… reactive
Because…
More reactive
Because they can attract the outer electron of the metal more easily
A displacement reaction is where…
A more reactive element displaces (pushes out) a less reactive element from a compound
The halogens displacement reactions are…
Radox reactions
As they gain electrons (reduction)
Whilst halide ions lose electrons (oxidation)
Chlorine displaces…
Bromine and iodine from salt solutions
