KS3 Chemistry

One of the most vital skills for young scientists (and especially chemists) is the ability to work safely in a lab environment with minimal intervention/help from teachers.  This topic therefore introduces Year 7s to the lab, and how to carry out practical work in it safely. 

This includes learning: 

• What hazard symbols are and how to manage the various risks of different chemicals

• Identifying and using scientific equipment correctly

• Measuring chemicals accurately

• How to follow written instructions accurately and without teacher assistance

The primary aim of this topic is to give students the basic understanding and practical skills they will need throughout their science education to carry out practical work as competent and independent learners. 

Knowledge Organiser 

RAG Sheet 

At KS2, students have already investigated the different types of materials that make up our world. They've classified these materials as solids, liquids and gasses based on their bulk properties, as well as looked at the basics of solubility and dissolving as reversible processes.

States of Matter in Year 7, students will learn about:

• The idea that all matter in the universe is made up of tiny particles called "atoms". 

• The different arrangements and interactions of atoms in solids, liquids and gases

• The properties of solids, liquids and gases (such as their states and melting/boiling points) and explain these properties using the particle model

• What is dissolving, solutions and solubility and what factors affect solubility

We build on KS2 knowledge as well by starting to explain the bulk properties of substance in terms of the arrangement of their particles and the forces between them.

We also go into more detail while investigating solubility, answering the interesting questions: "What is actually happening to particles when something dissolves?" and "How can we change how fast something dissolves?".

Knowledge Organiser

RAG sheet 

Not all atoms are created equal.

There are over 118 different types of atoms in our universe that we call "elements", all with different sizes and different properties.

Elements, Compounds and Mixtures builds on the simple particle model of matter students have come across in States of Matter. 

We now look at:

• How atoms come together to form new chemicals (compounds)

• How do we name different chemical compounds

• How scientist represent atoms of different elements with a single/pair of letters (it's chemical symbol), 

• How we combine chemical symbols to make a chemical formula

Students will learn to identify chemical symbols using the periodic table and use these to represent elements and compounds for a wide variety of chemicals they will come across in science and everyday life.

Knowledge Organiser

RAG sheet 

Chemical reactions are all around us. They happen every second of every day, and are how atoms rearrange themselves to make new chemicals and materials. 

In the previous topic students learned how we can work out the name of a chemical from it's chemical formula. 

In Chemical Reactions, students will learn:

• The differences between chemical reactions and physical changes

• The signs of a chemical reaction taking place

• How we can represent these chemical reactions using word equations 

• What exothermic and endothermic reactions are

• What the law of conservation of mass is and how to calculate the mass of a product made by a reaction

• What thermal decompositions are

Knowledge Organiser

RAG sheet 

It can be very hard to classify chemicals, especially in chemistry where nearly everything is either a colourless liquid or a white powder!

In the previous topic students learned how we can work out the name of a chemical from it's chemical formula. 

In Acids and Alkalis students will learn:

• The differences between an acid and an alkali

• How we can identify acids and alkalis using indicators

• How we can make salts by reacting acids and alkalis together

• How we can purify a salt

Knowledge Organiser

RAG sheet 

In Year 7, students were introduced to the idea that all matter in the universe is made up of atoms, and that the different arrangement of these atoms creates elements, compounds and mixtures. These different combinations of atoms make up everything we see and interact with everyday, including our own bodies!

In this topic students build on this knowledge of atoms and delve even deeper inside atoms.

Students will learn:

• What subatomic particles atoms themselves are made up of

• How these particles are arranged inside atoms

• How we can calculate the number of each particle using the periodic table

• What happens when atoms react with each other

This topic introduces key concepts for chemistry which will lay a  strong foundation for students to take on to GCSE Chemistry in Year 9.

In Year 7, students were introduced to chemical formulas, and the idea that all elements and compounds can be represented by combinations of letters and numbers.  

Students build on this understanding, as well as their knowledge of atomic structure from the last topic to explore specific groups and types of elements in the periodic table. We specifically study and investigate the properties and reactions of Group 1, 7 and 0 elements. 

In the real world, it is often very hard to find pure samples of chemicals. Most chemicals are mixed with other things. So, in order to get pure samples we need to be able to separate different mixtures of elements and compounds. 

Students have already looked at basic separation techniques as part of the KS2 syllabus (such as sieving, filtration and evaporation).

In this topic students will build on this knowledge to look at:

• How chemists can sperate mixtures of insoluble solids and liquids using filtration

• How chemists can separate mixtures of soluble solids and liquids using crystallization

• How chemists can separate mixtures of liquids using distillation

This topic will also introduce new key terminology to students. This will allow them to more accurately describe and explain the use of each method for specific mixtures, in terms of the properties of the chemicals they contain and the relative sizes of particles involved.

A lot of chemicals in chemistry look the same. Nearly everything is a colourless liquid or a white powder. It can be frustrating for scientists to not know what a chemical is (and possibly dangerous too!).

Therefore it is very important for scientists to be able to identify chemicals and what they're made of.

In the previous topic Separation Techniques, students have learned about how we can separate a mixture of different chemicals to get a pure sample. In this topic we now look at how we can analyze those chemicals we separate to find out exactly what they are and what elements they're made of.

In this topic students learn:

• How to use flame tests to identify metals

• How to identify what gas is given off by a reaction using simple gas tests 

• How to use chromatography to identify chemicals in a mixture (e.g. colours in a food dye)