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Olive Stevens
17/09/2025
Chemistry
Chemistry paper one aqa
9,194
•
17 Sept 2025
•
Chemistry Fun: Mixtures, Compounds, and Atoms for KS3 & GCSE AQA
Olive Stevens
@olivestevens_ssuw
1 / 10
Ionic Bonding and Periodic Table
This section explores ionic bonding, the properties of ionic compounds, and the organization of the periodic table.
Ionic Bonding
Ionic bonding occurs when metal atoms lose electrons to non-metal atoms:
Definition: An ion is an atom that has gained or lost electrons, resulting in a net electrical charge.
The formation of a giant ionic lattice is explained:
Highlight: Giant ionic lattices are structures formed by ionic compounds. They consist of a regular arrangement of positive and negative ions held together by strong electrostatic forces.
Properties of Ionic Compounds
Ionic compounds have distinct properties due to their structure:
- High melting points: Strong electrostatic forces require significant energy to break
- Conductivity: Solid ionic compounds do not conduct electricity, but molten or dissolved ionic compounds do
Example: Sodium chloride (table salt) is an example of an ionic compound with a giant ionic lattice structure.
The Periodic Table
The development and organization of the periodic table are discussed:
- Mendeleev's periodic table: Grouped elements by chemical properties, had gaps for undiscovered elements
- Modern periodic table: Ordered by atomic number, no gaps, metals on the left and non-metals on the right
Highlight: The development of the atomic model and discovery of subatomic particles greatly influenced the organization of the periodic table.
Element Groups and Their Properties
This section focuses on specific groups in the periodic table, particularly Group 0 (noble gases), Group 1 (alkali metals), and Group 7 (halogens).
Group 0: Noble Gases
Noble gases have unique properties due to their full outer electron shells:
Highlight: Noble gases are extremely unreactive and exist as single atoms, not forming molecules.
Properties of noble gases:
- Very unreactive (inert)
- Exist as single atoms
- Boiling points increase down the group
Group 1: Alkali Metals
Group 1 elements, also known as alkali metals, are highly reactive:
Vocabulary: Alkali metals are called so because they react with water to form alkaline solutions of their metal hydroxides.
Properties and reactions of Group 1 elements:
- One electron in their outer shell
- Very reactive
- Reactivity increases down the group
- React with oxygen, chlorine, and water
Example: Lithium + Water → Lithium hydroxide + Hydrogen
Group 7: Halogens
Group 7 elements, known as halogens, are non-metals with distinct properties:
Properties of halogens:
- Exist as diatomic molecules (e.g., F₂, Cl₂, Br₂, I₂)
- Melting and boiling points increase down the group
- Reactivity decreases down the group
Example: Fluorine is a gas at room temperature, while iodine is a solid.
Covalent Bonding and Giant Structures
This section introduces covalent bonding and the properties of giant covalent structures.
Covalent Bonding
Covalent bonding involves the sharing of electrons between non-metal atoms:
Definition: A covalent bond is formed when atoms share one or more pairs of electrons.
Giant Covalent Structures
Giant covalent structures are large networks of atoms held together by covalent bonds:
Properties of giant covalent structures:
- High melting and boiling points
- Strong covalent bonds between atoms
Highlight: The high melting and boiling points of giant covalent structures are due to the need to break numerous strong covalent bonds.
Example: Diamond and graphite are examples of giant covalent structures with different properties due to their atomic arrangements.
Mixtures and Atomic Structure
This section introduces the concept of mixtures and methods for separating them. It also delves into the development of atomic models and the structure of atoms.
Mixtures and Separation Methods
A mixture consists of two or more elements or compounds that are not chemically combined. Various methods can be used to separate mixtures based on their components:
Highlight: The five main processes used to separate mixtures are filtration, crystallization, simple distillation, fractional distillation, and paper chromatography.
Example: Filtration is used to separate an insoluble solid from a liquid, while crystallization separates a soluble solid from a solution.
Atomic Structure and Models
The section covers the evolution of atomic models, from Dalton's solid sphere to the nuclear model:
Definition: An atom is the smallest unit of matter that retains the properties of an element.
- Dalton's model: Solid, indivisible sphere
- Plum pudding model: Positive charge cloud with embedded electrons
- Bohr model: Electrons orbiting at fixed distances
- Nuclear model: Electrons orbiting the nucleus, but not at fixed distances
Vocabulary: Isotopes are atoms of the same element with different numbers of neutrons.
The document also explains the concept of relative atomic mass and how to calculate it.
Subatomic Particles
The properties of subatomic particles are described:
- Protons: Relative charge +1, relative mass 1
- Neutrons: Relative charge 0, relative mass 1
- Electrons: Relative charge -1, negligible mass
Highlight: The number of protons in an atom determines its atomic number and identity as a specific element.
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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Chemistry Fun: Mixtures, Compounds, and Atoms for KS3 & GCSE AQA
Olive Stevens
@olivestevens_ssuw
The document provides an in-depth overview of key chemistry concepts, focusing on atomic structure, bonding, and the periodic table. It covers topics such as separating mixtures, atomic models, ionic bonding, and properties of elements in different groups.
- Explains the... Show more
Ionic Bonding and Periodic Table
This section explores ionic bonding, the properties of ionic compounds, and the organization of the periodic table.
Ionic Bonding
Ionic bonding occurs when metal atoms lose electrons to non-metal atoms:
Definition: An ion is an atom that has gained or lost electrons, resulting in a net electrical charge.
The formation of a giant ionic lattice is explained:
Highlight: Giant ionic lattices are structures formed by ionic compounds. They consist of a regular arrangement of positive and negative ions held together by strong electrostatic forces.
Properties of Ionic Compounds
Ionic compounds have distinct properties due to their structure:
- High melting points: Strong electrostatic forces require significant energy to break
- Conductivity: Solid ionic compounds do not conduct electricity, but molten or dissolved ionic compounds do
Example: Sodium chloride (table salt) is an example of an ionic compound with a giant ionic lattice structure.
The Periodic Table
The development and organization of the periodic table are discussed:
- Mendeleev's periodic table: Grouped elements by chemical properties, had gaps for undiscovered elements
- Modern periodic table: Ordered by atomic number, no gaps, metals on the left and non-metals on the right
Highlight: The development of the atomic model and discovery of subatomic particles greatly influenced the organization of the periodic table.
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Element Groups and Their Properties
This section focuses on specific groups in the periodic table, particularly Group 0 (noble gases), Group 1 (alkali metals), and Group 7 (halogens).
Group 0: Noble Gases
Noble gases have unique properties due to their full outer electron shells:
Highlight: Noble gases are extremely unreactive and exist as single atoms, not forming molecules.
Properties of noble gases:
- Very unreactive (inert)
- Exist as single atoms
- Boiling points increase down the group
Group 1: Alkali Metals
Group 1 elements, also known as alkali metals, are highly reactive:
Vocabulary: Alkali metals are called so because they react with water to form alkaline solutions of their metal hydroxides.
Properties and reactions of Group 1 elements:
- One electron in their outer shell
- Very reactive
- Reactivity increases down the group
- React with oxygen, chlorine, and water
Example: Lithium + Water → Lithium hydroxide + Hydrogen
Group 7: Halogens
Group 7 elements, known as halogens, are non-metals with distinct properties:
Properties of halogens:
- Exist as diatomic molecules (e.g., F₂, Cl₂, Br₂, I₂)
- Melting and boiling points increase down the group
- Reactivity decreases down the group
Example: Fluorine is a gas at room temperature, while iodine is a solid.
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Covalent Bonding and Giant Structures
This section introduces covalent bonding and the properties of giant covalent structures.
Covalent Bonding
Covalent bonding involves the sharing of electrons between non-metal atoms:
Definition: A covalent bond is formed when atoms share one or more pairs of electrons.
Giant Covalent Structures
Giant covalent structures are large networks of atoms held together by covalent bonds:
Properties of giant covalent structures:
- High melting and boiling points
- Strong covalent bonds between atoms
Highlight: The high melting and boiling points of giant covalent structures are due to the need to break numerous strong covalent bonds.
Example: Diamond and graphite are examples of giant covalent structures with different properties due to their atomic arrangements.
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Mixtures and Atomic Structure
This section introduces the concept of mixtures and methods for separating them. It also delves into the development of atomic models and the structure of atoms.
Mixtures and Separation Methods
A mixture consists of two or more elements or compounds that are not chemically combined. Various methods can be used to separate mixtures based on their components:
Highlight: The five main processes used to separate mixtures are filtration, crystallization, simple distillation, fractional distillation, and paper chromatography.
Example: Filtration is used to separate an insoluble solid from a liquid, while crystallization separates a soluble solid from a solution.
Atomic Structure and Models
The section covers the evolution of atomic models, from Dalton's solid sphere to the nuclear model:
Definition: An atom is the smallest unit of matter that retains the properties of an element.
- Dalton's model: Solid, indivisible sphere
- Plum pudding model: Positive charge cloud with embedded electrons
- Bohr model: Electrons orbiting at fixed distances
- Nuclear model: Electrons orbiting the nucleus, but not at fixed distances
Vocabulary: Isotopes are atoms of the same element with different numbers of neutrons.
The document also explains the concept of relative atomic mass and how to calculate it.
Subatomic Particles
The properties of subatomic particles are described:
- Protons: Relative charge +1, relative mass 1
- Neutrons: Relative charge 0, relative mass 1
- Electrons: Relative charge -1, negligible mass
Highlight: The number of protons in an atom determines its atomic number and identity as a specific element.
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We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
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App Store
4.8/5
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user