CHEMISTRY PAPER 2 - Using this trend you can predict how going even more down the
TOPIC 6 – GROUPS (1, 7 & 0) IN THE PERIODIC TABLE group reactivity will increase more
GROUP 1 – ALKALI METALS 6.5 Explain this pattern in reactivity in terms of electronic
6.1 Explain why some elements can be classified as alkali configurations
metals (group 1), halogens (group 7) or noble gases (group 0), - Group 1 metals only have 1 electron on their outer shell so will
based on their position in the periodic table easily lose it.
Elements in the same group have the same number of electrons in - The more readily a metal loses its outer electron the more
their outer shell so have similar chemical properties. reactive it is
6.2 Recall that alkali metals: a) are soft b) have relatively low - As you go down group 1, the metals get more reactive. This is
melting points because the outer electron is more easily lost as it is further away
Alkali metals have one electron on the outer shell. from the nucleus (the atomic radius is larger) - so it's less strongly
They all have the following PHYSICAL properties: attracted to the nucleus and less energy is needed to remove it.
a) Low melting/boiling point (compared to other metals). GROUP 7 – HALOGENS
Melting/boiling points DECREASE as you go down the group - All halogens have 7 electrons on their outer shell & exist as
b) Very soft – they can be cut with a knife. They generally get DIATOMIC MOLECULES (eg Cl2, Br2, I2) as sharing one pair of
SOFTER as you go down the group electrons in a covalent bond allows them to get a full outer shell
c) density increase generally as you go down 6.6 Recall the colours and physical states of chlorine, bromine
6.3 Describe the reactions of lithium, sodium and potassium and iodine at room temperature
with water CHLORINE: green GAS
6.4 Describe the pattern in reactivity of the alkali metals, BROMINE: red-brown LIQUID which gives off an orange vapour
lithium, sodium and potassium, with water; and use this IODINE: dark-grey crystalline (clear) SOLID gives off purple vapour
pattern to predict the reactivity of other alkali metals when heated
- When alkali metals are put into water, they react vigorously 6.7 Describe the pattern in the physical properties of the
- The reaction ALWAYS produces a hydroxide of the metal & halogens, chlorine, bromine and iodine, and use this pattern to
hydrogen (the hydrogen can be tested for by squeaky pop): predict the physical properties of other halogens
SODIUM + WATER --> SODIUM HYDROXIDE + HYDROGEN As you go down the halogens (group 7):
- Group 1 metals reactivity with water (and dilute acid) increases 1) Melting & boiling points INCREASE.
as you go down the group as the outer electron is more easily lost. 2) REACTIVITY DECREASES
- LITHIUM: will move around fizzing furiously 3) The colour gets darker
- SODIUM & POTASSIUM: Do the same but also melt in the heat of
the reaction.
,This means you can predict properties of other halogens. EG: Halogens also react with HYDROGEN to form HYDROGEN
astatine is below iodine so it will be DARKER & have a HIGHER HALIDES.
melting/boiling point. Thus, it will be a dark-coloured SOLID - ‘Hydrogen Halides’ are SOLUBLE – they can dissolve in water to
6.8 Describe the chemical test for chlorine form ACIDIC SOLUTIONS. For example:
TEST FOR CHLORINE: Hold a piece of DAMP BLUE LITMUS PAPER H2 + Cl2 --> 2HCl
over the gas. If it is chlorine the litmus paper will turn RED for a HYDROGEN + CHLORINE --> HYDROGEN CHLORIDE
moment, then it will bleach (turn white). - Here the ‘hydrogen halide’ produced is Hydrogen chloride which
- The reason damp blue litmus paper turns RED for a moment is is a GAS & is NEUTRAL (pH of 7).
because the solution is acidic. Chlorine gas reacts with the water - As it is a ‘hydrogen halide’ it can dissolve in water to form an
on the DAMP litmus paper to form HCl which is an acid, thus the acidic solution. Hydrogen Chloride (gas) can be diluted in water to
litmus paper turns RED. form an acid: DILUTE HYDROCHLORIC ACID (HCl).
6.9 Describe the reactions of the halogens, chlorine, bromine - That is why we write ‘aqueous HCl’ to show it is in water and is
and iodine, with metals to form metal halides, and use this thus an acidic solution as just ‘HCl’ could be the neutral gas.
pattern to predict the reactions of other halogens 6.11 Describe the relative reactivity of the halogens chlorine,
Halogens react vigorously with some METALS (mostly alkali bromine and iodine, as shown by their displacement reactions
metals) to form salts called ‘METAL HALIDES’. They make an with halide ions in aqueous solution, and use this pattern to
IONIC BOND with the metal. Halogen higher up are MORE reactive predict the reactions of astatine
as they can attract the outer electron of the metal more easily as DISPLACEMENT REACTIONS
they have a smaller atom. - Group 7 elements take part in displacement reactions which is
EG: 2Na + Cl2 --> 2NaCl when a MORE REACTIVE element ‘pushes out’ (DISPLACES) a
SODIUM + CHLORINE --> SODIUM CHLORIDE LESS REACTIVE METAL from a compound.
- A ‘HALIDE' is a halogen that has gained an electron (it is an ion): - The halogen displacement reactions are REDOX REACTIONS.
Fluorine (atom) --> Fluoride (Ion) This is because the halogen gains an electron (REDUCTION) & the
Chlorine (atom) --> Chloride (Ion) halide ion loses an electron (OXIDATION).
Bromine (atom) --> Bromide (Ion) - For example, Chlorine is more reactive than bromine (it’s higher
6.10 Recall that the halogens, chlorine, bromine and iodine, up in the group):
form hydrogen halides which dissolve in water to form acidic
solutions, and use this pattern to predict the reactions of other
halogens - If you add chlorine water (aqueous solution) to potassium
bromide, the chlorine will displace the bromine.
,You can use displacement reactions to find the REACTIVITY Explained above ---^
TREND of halogens: 6.13 Explain the relative reactivity of the halogens in terms of
1) Measure a small amount of a halide salt solution (a halogen electronic configurations
bonded with a metal dissolved in water) into a test tube. - Halogens only need 1 more electron to get a full outer shell.
2) Add a few drops of a halogen solution to it and shake the tube - The easier it is for a halogen to attract an electron the more
3) If there IS a colour change a reaction has happened and the reactive it will be.
halogen has displaced the halide ions from the salt. If there IS - Thus reactivity decreases as you go down as it is HARDER to
NOT a colour change then no reaction has happened and the attract an electron as it is further away from the nucleus (the
halogen is less reactive than the halide and can’t displace it. atomic radius is larger)
4) Repeat the process using different combinations of halide salt GROUP 0 – NOBLE GASES
& halogen. 6.14 Explain why the noble gases are chemically inert,
compared with the other elements, in terms of their electronic
configurations
- Noble gases are INERT (unreactive)
- This is because they all have a FULL OUTER SHELL of electrons,
so they don’t easily lose/gain electrons
6.15 Explain how the uses of noble gases depend on their
- The table shows what should happen when you mix different inertness, low density and/or non-flammability
combinations of chlorine, bromine & iodine water with solutions - Noble gases are useful as they are inert & inflammable so can be
of the salts: potassium Chloride, potassium Bromide & potassium used in the atmosphere. Uses include:
Iodide. 1) FILAMENT LAMPS (LIGHT BUBLBS): The light bulb can’t have
- The table shows that CHLORINE can displace both Iodine & oxygen as it will corrode the filament. It also can’t be kept in a
Bromine. BROMINE can’t displace chlorine but it does displace complete vacuum as the filament will evaporate. Thus, it is filled
Iodine. Iodine can’t displace chlorine or iodine. with an inert gas from group 0 such as ARGON as it is NON-
- This shows a REACTIVITY TREND – halogens get less reactive as FLAMMABLE so stops the filament from burning
they go down. 2) HOT AIR BALLOONS: Helium is used as it is less dense than air.
- You can use this trend to predict how astatine will react – It is the It also is non-flammable so is much more safer than using
least reactive halogen so it won’t displace other halogens hydrogen which is flammable.
6.12 Explain why these displacement reactions are redox 3) LIGHTING: Noble gases are used in fluorescent lighting as well
reactions in terms of gain and loss of electrons, identifying as photography in which XENON is used as it gives off a white light
which of the substances are oxidised and which are reduced
, 6.16 Describe the pattern in the physical properties of some - Measuring cylinder (tall cylinder)
noble gases and use this pattern to predict the physical - Lab clamp (to hold the inverted measuring cylinder in the trough)
properties of other noble gases SETUP: 1) Gently push an end of the delivery tube through the hole
PROPPERTIES OF NOBLE GASES: of the bung till it is a few millimetres out the other side.
1) All are COLOURLESS gases at room temperature - Check it is AIRTIGHT by putting other end of delivery tube in
2) All are MONOATOMIC (made up of a single atomic) water and place bung on conical flask. Bubbles of water will be
3) As they are inert, they are INFLAMMABLE – won’t set on fire seen if it is airtight
4) Boiling/melting point & density INCREASE as you go down 2) GAS COLLECTION APPARATUS: Take a 100cm3 measuring
Group 0. cylinder filled with water and put a bung on it.
TOPIC 7 – RATES OF REACTION & ENERGY CHANGES - Invert the measuring cylinder in the trough (container of water)
RATES OF REACTION and clamp into place so that the lip of the measuring cylinder is
7.1 CORE PRACTICAL: Investigate the effects of changing the below the waterline of the trough.
conditions of a reaction on the rates of chemical reactions by: - The water in the TROUGH must NOT be too high or the water
a measuring the production of a gas (in the reaction between displaced will overflow
hydrochloric acid and marble chips) - TAKE OFF THE BUNG on the measuring cylinder.
b observing a colour change (in the reaction between sodium IMAGE A (Gas Collection apparatus) IMAGE B (fully set up)
thiosulfate and hydrochloric acid)
a) MEASURING THE PRODUCTION OF GAS - HCl & Marble chips
In this experiment, you are investigating the effects of:
a) Changing SURFACE AREA (size of marble chips)
b) Changing CONCENTRATION (of dilute HCl)
...on the rate of the reaction.
- The reaction is between HYDROCHLORIC ACID & marble chips
of CALCIUM CARBONATE. This will form WATER, CALCIUM
CHLORIDE & CARBON DIOXIDE GAS. The symbol equation is:
2HCl(aq) + CaCO3(s) --> CaCl2(s) + H2O + CO2(g)
- The amount of CO2 gas given off will be measured to find the rate
of reaction, so a gas measuring mechanism is needed.
EQUIPMENT: - Conical flask & bung (to stop gas escaping) that fits
- Delivery tube (to transport CO2 gas and measure it)
- Trough (a wide container filled with water NOT to the brim) NOTE: For gas collection a GAS SYRINGE may also be used
TOPIC 6 – GROUPS (1, 7 & 0) IN THE PERIODIC TABLE group reactivity will increase more
GROUP 1 – ALKALI METALS 6.5 Explain this pattern in reactivity in terms of electronic
6.1 Explain why some elements can be classified as alkali configurations
metals (group 1), halogens (group 7) or noble gases (group 0), - Group 1 metals only have 1 electron on their outer shell so will
based on their position in the periodic table easily lose it.
Elements in the same group have the same number of electrons in - The more readily a metal loses its outer electron the more
their outer shell so have similar chemical properties. reactive it is
6.2 Recall that alkali metals: a) are soft b) have relatively low - As you go down group 1, the metals get more reactive. This is
melting points because the outer electron is more easily lost as it is further away
Alkali metals have one electron on the outer shell. from the nucleus (the atomic radius is larger) - so it's less strongly
They all have the following PHYSICAL properties: attracted to the nucleus and less energy is needed to remove it.
a) Low melting/boiling point (compared to other metals). GROUP 7 – HALOGENS
Melting/boiling points DECREASE as you go down the group - All halogens have 7 electrons on their outer shell & exist as
b) Very soft – they can be cut with a knife. They generally get DIATOMIC MOLECULES (eg Cl2, Br2, I2) as sharing one pair of
SOFTER as you go down the group electrons in a covalent bond allows them to get a full outer shell
c) density increase generally as you go down 6.6 Recall the colours and physical states of chlorine, bromine
6.3 Describe the reactions of lithium, sodium and potassium and iodine at room temperature
with water CHLORINE: green GAS
6.4 Describe the pattern in reactivity of the alkali metals, BROMINE: red-brown LIQUID which gives off an orange vapour
lithium, sodium and potassium, with water; and use this IODINE: dark-grey crystalline (clear) SOLID gives off purple vapour
pattern to predict the reactivity of other alkali metals when heated
- When alkali metals are put into water, they react vigorously 6.7 Describe the pattern in the physical properties of the
- The reaction ALWAYS produces a hydroxide of the metal & halogens, chlorine, bromine and iodine, and use this pattern to
hydrogen (the hydrogen can be tested for by squeaky pop): predict the physical properties of other halogens
SODIUM + WATER --> SODIUM HYDROXIDE + HYDROGEN As you go down the halogens (group 7):
- Group 1 metals reactivity with water (and dilute acid) increases 1) Melting & boiling points INCREASE.
as you go down the group as the outer electron is more easily lost. 2) REACTIVITY DECREASES
- LITHIUM: will move around fizzing furiously 3) The colour gets darker
- SODIUM & POTASSIUM: Do the same but also melt in the heat of
the reaction.
,This means you can predict properties of other halogens. EG: Halogens also react with HYDROGEN to form HYDROGEN
astatine is below iodine so it will be DARKER & have a HIGHER HALIDES.
melting/boiling point. Thus, it will be a dark-coloured SOLID - ‘Hydrogen Halides’ are SOLUBLE – they can dissolve in water to
6.8 Describe the chemical test for chlorine form ACIDIC SOLUTIONS. For example:
TEST FOR CHLORINE: Hold a piece of DAMP BLUE LITMUS PAPER H2 + Cl2 --> 2HCl
over the gas. If it is chlorine the litmus paper will turn RED for a HYDROGEN + CHLORINE --> HYDROGEN CHLORIDE
moment, then it will bleach (turn white). - Here the ‘hydrogen halide’ produced is Hydrogen chloride which
- The reason damp blue litmus paper turns RED for a moment is is a GAS & is NEUTRAL (pH of 7).
because the solution is acidic. Chlorine gas reacts with the water - As it is a ‘hydrogen halide’ it can dissolve in water to form an
on the DAMP litmus paper to form HCl which is an acid, thus the acidic solution. Hydrogen Chloride (gas) can be diluted in water to
litmus paper turns RED. form an acid: DILUTE HYDROCHLORIC ACID (HCl).
6.9 Describe the reactions of the halogens, chlorine, bromine - That is why we write ‘aqueous HCl’ to show it is in water and is
and iodine, with metals to form metal halides, and use this thus an acidic solution as just ‘HCl’ could be the neutral gas.
pattern to predict the reactions of other halogens 6.11 Describe the relative reactivity of the halogens chlorine,
Halogens react vigorously with some METALS (mostly alkali bromine and iodine, as shown by their displacement reactions
metals) to form salts called ‘METAL HALIDES’. They make an with halide ions in aqueous solution, and use this pattern to
IONIC BOND with the metal. Halogen higher up are MORE reactive predict the reactions of astatine
as they can attract the outer electron of the metal more easily as DISPLACEMENT REACTIONS
they have a smaller atom. - Group 7 elements take part in displacement reactions which is
EG: 2Na + Cl2 --> 2NaCl when a MORE REACTIVE element ‘pushes out’ (DISPLACES) a
SODIUM + CHLORINE --> SODIUM CHLORIDE LESS REACTIVE METAL from a compound.
- A ‘HALIDE' is a halogen that has gained an electron (it is an ion): - The halogen displacement reactions are REDOX REACTIONS.
Fluorine (atom) --> Fluoride (Ion) This is because the halogen gains an electron (REDUCTION) & the
Chlorine (atom) --> Chloride (Ion) halide ion loses an electron (OXIDATION).
Bromine (atom) --> Bromide (Ion) - For example, Chlorine is more reactive than bromine (it’s higher
6.10 Recall that the halogens, chlorine, bromine and iodine, up in the group):
form hydrogen halides which dissolve in water to form acidic
solutions, and use this pattern to predict the reactions of other
halogens - If you add chlorine water (aqueous solution) to potassium
bromide, the chlorine will displace the bromine.
,You can use displacement reactions to find the REACTIVITY Explained above ---^
TREND of halogens: 6.13 Explain the relative reactivity of the halogens in terms of
1) Measure a small amount of a halide salt solution (a halogen electronic configurations
bonded with a metal dissolved in water) into a test tube. - Halogens only need 1 more electron to get a full outer shell.
2) Add a few drops of a halogen solution to it and shake the tube - The easier it is for a halogen to attract an electron the more
3) If there IS a colour change a reaction has happened and the reactive it will be.
halogen has displaced the halide ions from the salt. If there IS - Thus reactivity decreases as you go down as it is HARDER to
NOT a colour change then no reaction has happened and the attract an electron as it is further away from the nucleus (the
halogen is less reactive than the halide and can’t displace it. atomic radius is larger)
4) Repeat the process using different combinations of halide salt GROUP 0 – NOBLE GASES
& halogen. 6.14 Explain why the noble gases are chemically inert,
compared with the other elements, in terms of their electronic
configurations
- Noble gases are INERT (unreactive)
- This is because they all have a FULL OUTER SHELL of electrons,
so they don’t easily lose/gain electrons
6.15 Explain how the uses of noble gases depend on their
- The table shows what should happen when you mix different inertness, low density and/or non-flammability
combinations of chlorine, bromine & iodine water with solutions - Noble gases are useful as they are inert & inflammable so can be
of the salts: potassium Chloride, potassium Bromide & potassium used in the atmosphere. Uses include:
Iodide. 1) FILAMENT LAMPS (LIGHT BUBLBS): The light bulb can’t have
- The table shows that CHLORINE can displace both Iodine & oxygen as it will corrode the filament. It also can’t be kept in a
Bromine. BROMINE can’t displace chlorine but it does displace complete vacuum as the filament will evaporate. Thus, it is filled
Iodine. Iodine can’t displace chlorine or iodine. with an inert gas from group 0 such as ARGON as it is NON-
- This shows a REACTIVITY TREND – halogens get less reactive as FLAMMABLE so stops the filament from burning
they go down. 2) HOT AIR BALLOONS: Helium is used as it is less dense than air.
- You can use this trend to predict how astatine will react – It is the It also is non-flammable so is much more safer than using
least reactive halogen so it won’t displace other halogens hydrogen which is flammable.
6.12 Explain why these displacement reactions are redox 3) LIGHTING: Noble gases are used in fluorescent lighting as well
reactions in terms of gain and loss of electrons, identifying as photography in which XENON is used as it gives off a white light
which of the substances are oxidised and which are reduced
, 6.16 Describe the pattern in the physical properties of some - Measuring cylinder (tall cylinder)
noble gases and use this pattern to predict the physical - Lab clamp (to hold the inverted measuring cylinder in the trough)
properties of other noble gases SETUP: 1) Gently push an end of the delivery tube through the hole
PROPPERTIES OF NOBLE GASES: of the bung till it is a few millimetres out the other side.
1) All are COLOURLESS gases at room temperature - Check it is AIRTIGHT by putting other end of delivery tube in
2) All are MONOATOMIC (made up of a single atomic) water and place bung on conical flask. Bubbles of water will be
3) As they are inert, they are INFLAMMABLE – won’t set on fire seen if it is airtight
4) Boiling/melting point & density INCREASE as you go down 2) GAS COLLECTION APPARATUS: Take a 100cm3 measuring
Group 0. cylinder filled with water and put a bung on it.
TOPIC 7 – RATES OF REACTION & ENERGY CHANGES - Invert the measuring cylinder in the trough (container of water)
RATES OF REACTION and clamp into place so that the lip of the measuring cylinder is
7.1 CORE PRACTICAL: Investigate the effects of changing the below the waterline of the trough.
conditions of a reaction on the rates of chemical reactions by: - The water in the TROUGH must NOT be too high or the water
a measuring the production of a gas (in the reaction between displaced will overflow
hydrochloric acid and marble chips) - TAKE OFF THE BUNG on the measuring cylinder.
b observing a colour change (in the reaction between sodium IMAGE A (Gas Collection apparatus) IMAGE B (fully set up)
thiosulfate and hydrochloric acid)
a) MEASURING THE PRODUCTION OF GAS - HCl & Marble chips
In this experiment, you are investigating the effects of:
a) Changing SURFACE AREA (size of marble chips)
b) Changing CONCENTRATION (of dilute HCl)
...on the rate of the reaction.
- The reaction is between HYDROCHLORIC ACID & marble chips
of CALCIUM CARBONATE. This will form WATER, CALCIUM
CHLORIDE & CARBON DIOXIDE GAS. The symbol equation is:
2HCl(aq) + CaCO3(s) --> CaCl2(s) + H2O + CO2(g)
- The amount of CO2 gas given off will be measured to find the rate
of reaction, so a gas measuring mechanism is needed.
EQUIPMENT: - Conical flask & bung (to stop gas escaping) that fits
- Delivery tube (to transport CO2 gas and measure it)
- Trough (a wide container filled with water NOT to the brim) NOTE: For gas collection a GAS SYRINGE may also be used
