Paper 2 Flashcards
What elements are in the halogens? (Answer in order from top of group to bottom)
Fl fluorine (g) Cl chlorine (g) Br Bromine (l) I Iodine (s) At Astatine (?)
What group are the halogens in and what does this tell us about them?
Group 7
Therefore have 7 electrons in their outer shell
What happens to the melting and boiling point as you go down group 7?
The melting and boiling point of halogens increase/get higher as you go down the group
What happens to the reactivity as you go down group 7 and why?
It gets less reactive because they have more shells further down the group and therefore the electrostatic forces of attraction are weaker and electrons are harder to pull in.
Halogens exist as diatomic molecules meaning?
They only exist as two atoms covalently(shared electrons) bonded together as a molecule. For example,
Fluorine exists as F[2] and chlorine exists as Cl[2]. This is because they both need one more electron to have a full outer shell and therefore can covalently bond
Metal + halogen –>
Metal halide
E.g Fluorine + magnesium –> magnesium fluorIDE
What type of bonding occurs between metals and non metals?
Ionic bonding so the metal will give electrons to the non metal and therefor give the non metal a negative charge
What are the colours of the halogens? And what is the trend? (As a gas?
Fluorine is pale yellow
Chlorine is pale yellow- green
Bromine is orange-brown
Iodine is violet
When do halogens take part in displacement reactions?
When reacting with halide salts e.g potassium iodide that have a halide that is less reactive than the halogen
What is oxidation?
Loss of electrons ( e.g bromide ions have lost electrons so have been oxidised to Bromine during the reaction with chlorine and potassium bromide)
What is reduction?
Gaining electrons e.g chlorine ions gain electrons so have been reduced to Chlorine- ions during the reaction with chlorine and potassium bromide
What are group 1 metals called?
Alkali metals
What are the properties of an alkali metal?
- soft/malleable
- low density
- react with water and oxygen
- toxic
- shiny
In group 1 what happens to the reactivity as you go down the group?
It gets more reactive because there are more shells and therefore the electrostatic forces of attraction are weaker and electrons can be lost easier
Where are the group 0 elements located in the periodic table?
The far right
What are the group 0 elements more commonly known as?
Noble gases
What is special about the reactivity of the noble gases?
They are in reactive due to a full outer shell
What are the uses of the group 0 elements?
Helium is used in balloons
Radon is used in hospitals for gamma rays
Xenon is used in fluorescent bulbs
What elements (in order) are in the group 1?
Li lithium Na sodium K potassium Rb rubidium Cs caesium Ft francium
What elements are in group 0? In order
He helium Ne neon Ar argon Kr krypton Xe xenon Rn radon
How many electrons do group 2 elements have in their outer shell?
2 dumbass
What happens to the reactivity of group 2 elements as you go down the group and why?
The reactivity increases because the attraction between the 2 electrons they need to lose and the nucleus grows weaker and therefor can lose those two electrons easier
What do all group 2 elements have in common?
- all react with water
- have 2 electrons in their outer shell
Why can atoms lose electrons easier if they have more shells?
Because they have weaker electrostatic forces of attraction
How does temperature affect the rate of reaction?
It increases because as the temperature increases, the atoms start to vibrate due to the increase in energy.
This results in more collisions between them and the reactant and therefore more successful collisions
How catalysts affect the rate of reaction?
They speed up rates of reaction without getting used up themselves. They do this by lowering the activation energy required, therefore particles don’t need as much energy when colliding to react and therefore there are more successful collisions.
How does increasing surface area affect the rate of reaction?
It speeds up the reaction by making more particles available to the reactant to react making more collisions and hence, more successful collisions.
How does increasing pressure affect the rate of reaction?
It increases because there is an increase in the chance of particles colliding because there is more particles to space available and therefore there more frequent collisions and hence, more successful collisions.
How does increasing the concentration affect the rate of reaction?
It increases the rate of reaction as there are mor particles available to react in the same volume so there is a greater chance of the particles colliding and hence more successful collisions.
How do you work out rate of reaction?
Formula
Volume produced/time taken
How do you work out average rate of reaction from a graph?
Draw a tangent to the curve
Draw a vertical line and horizontal line to form a right-angled triangle with the line from step 1.
Then do x/y
(Change in volume produced/time)
What are the colours of the halogens?
Fluorine - pale yellow
Chlorine- green
Bromine - brown
Iodine - purple
What are alcohols?
Alcohols are a family of organic (carbon-based) compounds. They all contain the –OH group and this is generally responsible for their chemical properties and reactions.
What are the uses of methanol?
-Methanol can be used as a chemical ‘feedstock’ (starting material for other chemical reactions)
-in anti-freeze and in the production of biodiesel.
.
What are the uses ethanol?
Ethanol can be used as a solvent and as a fuel
What are the physical properties of short chain alcohols?
- short-chain alcohols like methanol and ethanol have a low boiling point (ie lower than water) because they have weak intermolecular forces which are easily overcome.
- Alcohols have higher boiling points than their corresponding alkane (eg ethanol has a higher boiling point than ethane) because the –OH group has the effect of strengthening the intermolecular forces.
- short chain alcohols are very soluble in water because of the effect of the –OH group that is strongly attracted to water molecules.
What are the physical properties of long chain alcohols?
- higher boiling points than the short chain molecules
- less soluble than the short chain because they behave more like alkanes and float on the surface