What collective name is given to the elements in Group 2 of the Periodic Table?
Alkaline earth metals
Examples include Mg, Ca, Sr and Ba.
What happens to atomic radius as you move down Group 2 from Mg to Ba?
Increases
Additional electron shells increase the size of the atoms.
Fill in the blank:
The first ionisation energy of Group 2 elements generally _______ down the group.
decreases
Increased distance and shielding reduce attraction to the outer electron.
True or False:
The reactivity of Group 2 metals increases down the group.
True
Lower ionisation energies make electron loss easier.
What type of bonding holds atoms together in Group 2 metals?
Metallic bonding
Positive ions are surrounded by delocalised electrons in a lattice.
True or False:
Magnesium reacts rapidly with cold water.
False
Magnesium reacts very slowly with cold water but reacts faster with steam.
Fill in the blank:
Magnesium reacts with steam to produce magnesium _______ and hydrogen.
oxide
Mg + H2O (steam) → MgO + H2.
What trend occurs in the solubility of Group 2 hydroxides down the group?
Increases
For example, Mg(OH)2 is sparingly soluble while Ba(OH)2 is much more soluble.
True or False:
Magnesium hydroxide is used in medicine as an antacid.
True
It neutralises excess stomach acid.
What agricultural substance is used to neutralise acidic soils?
Calcium hydroxide
It increases soil pH to improve crop growth.
Fill in the blank:
The solubility of Group 2 _______ decreases down the group.
sulfates
BaSO4 is insoluble in water.
What reagent is used to test for sulfate ions in solution?
Acidified barium chloride
A white precipitate of BaSO4 confirms sulfate ions.
What property of magnesium hydroxide allows it to be used as an antacid?
It is sparingly soluble in water.
How does melting point change down Group 2?
It generally decreases down the group.
How is titanium extracted from TiCl₄ using magnesium?
TiCl₄ + 2Mg → Ti + 2MgCl₂
Why does the melting point of Group 2 elements decrease down the group?
The ions get larger, so charge density decreases and metallic bonding becomes weaker.
Weaker electrostatic attraction between positive ions and delocalised electrons.
What is the role of magnesium in extracting titanium from TiCl₄?
It acts as a reducing agent.
Why are CaO or CaCO₃ used in flue gas treatment?
To remove SO₂ (a pollutant)
What are the equations for removing SO₂ using CaO/CaCO₃?
CaO + SO₂ → CaSO₃
CaCO₃ + SO₂ → CaSO₃ + CO₂
Why is SO₂ removed from flue gases?
To reduce acid rain and environmental damage.
What is BaSO₄ used for in medicine?
Barium meal- lines the gut in X rays
It is insoluble so it does not release toxic Ba²⁺ ions, and it absorbs X-rays due to its high density, outlining the gut.
What is the equation for the sulfate test using BaCl₂?
Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
Why is the solution acidified when testing for sulfate ions?
To remove carbonate impurities that could also form a precipitate
What would happen if the solution was not acidified?
Carbonate ions could form BaCO₃(s), giving a false positive.
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3.1.1 Atomic structure50
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3.1.2 Amount of substance47
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3.1.3 Bonding90
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3.1.4 Energetics62
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3.1.5 Kinetics55
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3.1.6 Equilibria & Kc24
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3.1.7 Redox equations17
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3.1.8 Thermodynamics27
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3.1.9 Rate equations24
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3.1.10 Kp12
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3.1.11 Electrode potentials46
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3.1.12 Acids and bases69
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3.2.1 Periodicity22
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3.2.2 Group 2 metals24
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3.2.3 Group 7 (halogens)31
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3.2.4 Period 3 oxides35
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3.2.5 Transition metals95
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3.2.6 Ions in aqueous solution39
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3.3.1 Intro to organic chemistry42
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3.3.2 Alkanes49
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3.3.3 Halogenoalkanes36
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3.3.4 Alkenes36
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3.3.5 Alcohols43
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3.3.6 Organic analysis36
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3.3.7 Optical isomerism12
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3.3.8 Aldehydes & ketones20
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3.3.9 Carboxylic acids & derivatives25
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3.3.10 Aromatic chemistry29
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3.3.11 Amines41
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3.3.12 Polymers24
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3.3.13 Amino acids, proteins, DNA61
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3.3.14 Organic synthesis12
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3.3.15 NMR spectroscopy14
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3.3.16 Chromatography12
