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Cool AQA A Level Chemistry Notes for Periodicity and Group 7 + More!

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Cool AQA A Level Chemistry Notes for Periodicity and Group 7 + More!

Periodicity in A-Level Chemistry: Key Concepts and Trends

This document covers essential topics in periodicity for AQA A-Level Chemistry, including:

  • Periodic table structure and trends
  • Ionization energies and atomic radii
  • Properties of Group 2 and Group 7 elements
  • Reactivity patterns and applications

Key points:

  • Periodicity refers to recurring trends in element properties
  • Atomic size, melting point, and reactivity show clear periodic trends
  • Ionization energies provide evidence for electron shell structure
  • Group 2 and 7 elements display characteristic chemical behaviors

23/03/2023

321

Overall Summary

Periodicity A Level Chemistry explores recurring trends in elemental properties across the periodic table. This comprehensive guide covers:

  • Structure and organization of the periodic table
  • Trends in atomic radii, melting points, and boiling points
  • Ionisation energy patterns and their relationship to electron configuration
  • Characteristic properties and reactions of Group 2 (alkaline earth metals) and Group 7 (halogens) elements
  • Applications of Group 2 and 7 compounds

Key concepts include:

  • Atomic size decreases across periods and increases down groups
  • First ionization energy generally increases across periods and decreases down groups
  • Group 2 reactivity with water increases down the group
  • Group 7 oxidizing ability decreases down the group
  • Displacement reactions demonstrate relative reactivity of halogens

This guide provides in-depth explanations of periodic trends, supported by data, diagrams, and real-world examples to aid understanding of AQA A Level chemistry Periodicity.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Page 3: Group VII Elements (Part 1)

This page delves into the properties of Group VII elements, also known as halogens, in Group 7 AQA A Level Chemistry. Key points include:

The concept of mean bond enthalpy is introduced, with a graph showing the trend across the halogen group. Fluorine's unexpectedly low F-F bond enthalpy is explained by electron repulsion between lone pairs.

Definition: Displacement reaction is a type of reaction in which part of one reactant is replaced by another reactant.

Vocabulary: Electronegativity is the power of an atom to attract the electrons in a covalent bond.

Physical properties of halogens are tabulated, including atomic number, electronegativity, atomic radius, and melting/boiling points. The trend in electronegativity decreases down the group.

Example: The physical states of halogens vary: F₂ and Cl₂ are gases, Br₂ is a liquid, and I₂ is a solid at room temperature.

The page concludes with a discussion of the oxidizing abilities of halogens, which decrease down the group. This is demonstrated through displacement reactions.

Highlight: Fluorine's reactivity with water prevents investigation of its oxidizing ability in aqueous solution.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Page 4: Group VII Elements (Part 2)

This page continues the discussion of Group VII elements, focusing on the reactivity of halide ions and chlorine in Group 7 reactions A Level Chemistry. Key points include:

The reducing strength of halide ions increases down the group, which is the opposite trend to the oxidizing ability of the halogens themselves.

Vocabulary: Disproportionation is a type of redox reaction where a species is simultaneously oxidized and reduced.

Definition: A precipitate (ppt) is an insoluble solid that forms and separates from the solution during a chemical reaction.

The page introduces tests for halide ions using silver nitrate solution, which produces characteristic colored precipitates:

  • Chloride ions produce a white precipitate
  • Bromide ions produce a cream precipitate
  • Iodide ions produce a yellow precipitate

Example: The halide ion tests can be used to identify unknown halide salts in solution.

The relative reducing strength of halide ions is demonstrated through their reactions with chlorine water. Chlorine water turns orange with bromide ions and brown with iodide ions, displacing the less reactive halogens.

Highlight: The reactions of halide ions with concentrated sulfuric acid provide further evidence of their relative reducing strengths.

This page provides essential information for understanding halogen chemistry in Group 7 A Level Chemistry OCR and other exam boards.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Page 1: Introduction to Periodicity

This page introduces key concepts in Periodicity Chemistry A Level, including:

The periodic table is organized based on atomic structure, with elements classified into s, p, d, and f blocks. Periodic trends are explained for properties like melting point, boiling point, and atomic radius across Period 3 elements. The page also covers ionization energy trends across periods and down groups.

Definition: Periodicity is the quality or character of being periodic; the tendency to recur at intervals.

Vocabulary: First ionization energy is the energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms.

Example: Atomic radius decreases across each period and increases down a group due to changes in nuclear charge and electron shielding.

Highlight: The periodic table's structure reflects electron configurations, with s, p, d, and f blocks corresponding to the orbital types.

A graph illustrates the trend in first ionization energies across the first 20 elements, showing the periodic nature of this property. The page also includes a visual representation of trends in various properties across the periodic table, such as atomic and ionic radii, electronegativity, and melting/boiling points.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Page 2: Group II Elements

This page focuses on the properties and reactions of Group II elements in the AQA A level Periodic Table, also known as alkaline earth metals. It covers:

Physical properties of Group II elements show clear trends as you move down the group. Atomic radius increases while first ionization energy and melting point decrease. The page provides specific data for magnesium, calcium, strontium, and barium.

Highlight: Reactivity with water increases down Group II, with magnesium reacting slowly with liquid water but rapidly with steam.

The solubility of Group II compounds is discussed, noting that hydroxide solubility increases down the group while sulfate solubility decreases.

Example: Mg(OH)₂, known as milk of magnesia, is used to treat indigestion and heartburn.

Vocabulary: Thermal decomposition refers to the breakdown of compounds by heat, forming metal oxides and carbon dioxide for Group II carbonates.

The page concludes with a table of applications for Group II compounds, demonstrating their importance in medicine and environmental management.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

View

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Knowunity is the #1 education app in five European countries

Knowunity has been named a featured story on Apple and has regularly topped the app store charts in the education category in Germany, Italy, Poland, Switzerland, and the United Kingdom. Join Knowunity today and help millions of students around the world.

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Lena, iOS user

I love this app ❤️ I actually use it every time I study.

Can't find what you're looking for? Explore other subjects.

Knowunity is the #1 education app in five European countries

Knowunity has been named a featured story on Apple and has regularly topped the app store charts in the education category in Germany, Italy, Poland, Switzerland, and the United Kingdom. Join Knowunity today and help millions of students around the world.

Ranked #1 Education App

Download in

Google Play

Download in

App Store

Knowunity is the #1 education app in five European countries

4.9+

Average app rating

13 M

Pupils love Knowunity

#1

In education app charts in 11 countries

950 K+

Students have uploaded notes

Still not convinced? See what other students are saying...

iOS User

I love this app so much, I also use it daily. I recommend Knowunity to everyone!!! I went from a D to an A with it :D

Philip, iOS User

The app is very simple and well designed. So far I have always found everything I was looking for :D

Lena, iOS user

I love this app ❤️ I actually use it every time I study.

View

Cool AQA A Level Chemistry Notes for Periodicity and Group 7 + More!

Cool AQA A Level Chemistry Notes for Periodicity and Group 7 + More!

Periodicity in A-Level Chemistry: Key Concepts and Trends

This document covers essential topics in periodicity for AQA A-Level Chemistry, including:

  • Periodic table structure and trends
  • Ionization energies and atomic radii
  • Properties of Group 2 and Group 7 elements
  • Reactivity patterns and applications

Key points:

  • Periodicity refers to recurring trends in element properties
  • Atomic size, melting point, and reactivity show clear periodic trends
  • Ionization energies provide evidence for electron shell structure
  • Group 2 and 7 elements display characteristic chemical behaviors

23/03/2023

321

Overall Summary

Periodicity A Level Chemistry explores recurring trends in elemental properties across the periodic table. This comprehensive guide covers:

  • Structure and organization of the periodic table
  • Trends in atomic radii, melting points, and boiling points
  • Ionisation energy patterns and their relationship to electron configuration
  • Characteristic properties and reactions of Group 2 (alkaline earth metals) and Group 7 (halogens) elements
  • Applications of Group 2 and 7 compounds

Key concepts include:

  • Atomic size decreases across periods and increases down groups
  • First ionization energy generally increases across periods and decreases down groups
  • Group 2 reactivity with water increases down the group
  • Group 7 oxidizing ability decreases down the group
  • Displacement reactions demonstrate relative reactivity of halogens

This guide provides in-depth explanations of periodic trends, supported by data, diagrams, and real-world examples to aid understanding of AQA A Level chemistry Periodicity.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

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Page 3: Group VII Elements (Part 1)

This page delves into the properties of Group VII elements, also known as halogens, in Group 7 AQA A Level Chemistry. Key points include:

The concept of mean bond enthalpy is introduced, with a graph showing the trend across the halogen group. Fluorine's unexpectedly low F-F bond enthalpy is explained by electron repulsion between lone pairs.

Definition: Displacement reaction is a type of reaction in which part of one reactant is replaced by another reactant.

Vocabulary: Electronegativity is the power of an atom to attract the electrons in a covalent bond.

Physical properties of halogens are tabulated, including atomic number, electronegativity, atomic radius, and melting/boiling points. The trend in electronegativity decreases down the group.

Example: The physical states of halogens vary: F₂ and Cl₂ are gases, Br₂ is a liquid, and I₂ is a solid at room temperature.

The page concludes with a discussion of the oxidizing abilities of halogens, which decrease down the group. This is demonstrated through displacement reactions.

Highlight: Fluorine's reactivity with water prevents investigation of its oxidizing ability in aqueous solution.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

Sign up to get unlimited access to thousands of study materials. It's free!

Access to all documents

Join milions of students

Improve your grades

By signing up you accept Terms of Service and Privacy Policy

Page 4: Group VII Elements (Part 2)

This page continues the discussion of Group VII elements, focusing on the reactivity of halide ions and chlorine in Group 7 reactions A Level Chemistry. Key points include:

The reducing strength of halide ions increases down the group, which is the opposite trend to the oxidizing ability of the halogens themselves.

Vocabulary: Disproportionation is a type of redox reaction where a species is simultaneously oxidized and reduced.

Definition: A precipitate (ppt) is an insoluble solid that forms and separates from the solution during a chemical reaction.

The page introduces tests for halide ions using silver nitrate solution, which produces characteristic colored precipitates:

  • Chloride ions produce a white precipitate
  • Bromide ions produce a cream precipitate
  • Iodide ions produce a yellow precipitate

Example: The halide ion tests can be used to identify unknown halide salts in solution.

The relative reducing strength of halide ions is demonstrated through their reactions with chlorine water. Chlorine water turns orange with bromide ions and brown with iodide ions, displacing the less reactive halogens.

Highlight: The reactions of halide ions with concentrated sulfuric acid provide further evidence of their relative reducing strengths.

This page provides essential information for understanding halogen chemistry in Group 7 A Level Chemistry OCR and other exam boards.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

Sign up to get unlimited access to thousands of study materials. It's free!

Access to all documents

Join milions of students

Improve your grades

By signing up you accept Terms of Service and Privacy Policy

Page 1: Introduction to Periodicity

This page introduces key concepts in Periodicity Chemistry A Level, including:

The periodic table is organized based on atomic structure, with elements classified into s, p, d, and f blocks. Periodic trends are explained for properties like melting point, boiling point, and atomic radius across Period 3 elements. The page also covers ionization energy trends across periods and down groups.

Definition: Periodicity is the quality or character of being periodic; the tendency to recur at intervals.

Vocabulary: First ionization energy is the energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms.

Example: Atomic radius decreases across each period and increases down a group due to changes in nuclear charge and electron shielding.

Highlight: The periodic table's structure reflects electron configurations, with s, p, d, and f blocks corresponding to the orbital types.

A graph illustrates the trend in first ionization energies across the first 20 elements, showing the periodic nature of this property. The page also includes a visual representation of trends in various properties across the periodic table, such as atomic and ionic radii, electronegativity, and melting/boiling points.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

Sign up to get unlimited access to thousands of study materials. It's free!

Access to all documents

Join milions of students

Improve your grades

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Page 2: Group II Elements

This page focuses on the properties and reactions of Group II elements in the AQA A level Periodic Table, also known as alkaline earth metals. It covers:

Physical properties of Group II elements show clear trends as you move down the group. Atomic radius increases while first ionization energy and melting point decrease. The page provides specific data for magnesium, calcium, strontium, and barium.

Highlight: Reactivity with water increases down Group II, with magnesium reacting slowly with liquid water but rapidly with steam.

The solubility of Group II compounds is discussed, noting that hydroxide solubility increases down the group while sulfate solubility decreases.

Example: Mg(OH)₂, known as milk of magnesia, is used to treat indigestion and heartburn.

Vocabulary: Thermal decomposition refers to the breakdown of compounds by heat, forming metal oxides and carbon dioxide for Group II carbonates.

The page concludes with a table of applications for Group II compounds, demonstrating their importance in medicine and environmental management.

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

Sign up to get unlimited access to thousands of study materials. It's free!

Access to all documents

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Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

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Access to all documents

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Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

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Access to all documents

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Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

Sign up to get unlimited access to thousands of study materials. It's free!

Access to all documents

Join milions of students

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Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

Sign up to get unlimited access to thousands of study materials. It's free!

Access to all documents

Join milions of students

Improve your grades

By signing up you accept Terms of Service and Privacy Policy

Unit 1: Periodicity
1. Keywords
Periodicity
First ionisation
energy
Second
ionisation
energy:
Successive
ionisation
energies:
Atomic radius

Register

Sign up to get unlimited access to thousands of study materials. It's free!

Access to all documents

Join milions of students

Improve your grades

By signing up you accept Terms of Service and Privacy Policy

Can't find what you're looking for? Explore other subjects.

Knowunity is the #1 education app in five European countries

Knowunity has been named a featured story on Apple and has regularly topped the app store charts in the education category in Germany, Italy, Poland, Switzerland, and the United Kingdom. Join Knowunity today and help millions of students around the world.

Ranked #1 Education App

Download in

Google Play

Download in

App Store

Knowunity is the #1 education app in five European countries

4.9+

Average app rating

13 M

Pupils love Knowunity

#1

In education app charts in 11 countries

950 K+

Students have uploaded notes

Still not convinced? See what other students are saying...

iOS User

I love this app so much, I also use it daily. I recommend Knowunity to everyone!!! I went from a D to an A with it :D

Philip, iOS User

The app is very simple and well designed. So far I have always found everything I was looking for :D

Lena, iOS user

I love this app ❤️ I actually use it every time I study.