Unit B: Matter and Chemical Change

 Learning Targets

Pre-assessment: What do you know?


Figure B.P.1 – Scientists describe substances with physical and chemical properties.

Figure B.P.2 – Scientists use symbols to name chemical substances.

The universe is made of matter. People in the past did not know as much about matter as we do today. Human understanding of matter improved after we developed better observation tools. We now know that all matter is made from tiny particles called atoms. Some types of matter contain just one type of atom, while other types of matter contain many connected atoms.

Figure B.P.3 – We use models to show atoms connected to other atoms. This is a model of a water molecule.

To communicate about and organize matter, scientists have developed rules to name different types of matter.

We describe matter by its properties, and how it interacts with other types of matter. In chemical reactions, matter can change into different substances. Scientists use their knowledge of matter and chemical change to create new substances that are useful to humans. For example, medicines, plastics, and computer chips are all developed based on scientific knowledge of atoms.

How do we name all the different types of matter? Why are there different types of atoms? How do particles interact to form new substances?

To learn more about how humans can heal make new chemicals, we must first understand matter and chemical change, and how the particles in a substance affect its properties.


Figure B.P.4 – The periodic table organizes different types of matter.

Figure B.P.5 – Some chemical reactions release heat.

Pre-assessment Questions & Hints

Step 1: The Questions


This short pre-assessment is to find out what you might already know about the topic of matter and chemical change. Below are four questions. Think about them! If you need a hint, click on the question.

Optional: If you would like a place to write your answers, download this document. If you prefer to use a Google Drive or PDF version of this pre-assessment, click here.

Think about what you observe when combining vinegar and baking soda, compared to combining vinegar and water.
Think about where you might have seen these symbols on a box or container.
Think about what substances are necessary during rusting and burning.

Step 2: The Answers

 Click each of the suggested answers below – how do they compare to your thoughts and answers?

A physical change can change the appearance of a substance, but it does not change the particles of the substance. Some physical changes include dissolving and changes of state.

A chemical change creates a substance with properties different from the original substance. Some signs of a chemical change are a colour change, formation of a gas or solid, heating or cooling without changing the temperature, and a new smell.
Protons, electrons, and neutrons are the smaller particles located inside atoms.
NaCl stands for sodium chloride, which is table salt. CO2 stands for carbon dioxide. NaCl is an ionic compound, while CO2 is a molecular compound.
Both a rusting car and a burning candle are chemical reactions that require oxygen.

Step 3: Check In With Your Teacher

The start of a new unit is a great time to touch base with your teacher! Here are just a few reasons to consider contacting your teacher:

  1. Perhaps you found this pre-assessment quiz very easy because you have studied this material before, such as at another school. If so, it's important to tell your teacher.

  2. It's very good for your teacher to know you are starting a new unit; it will give them a good idea of your progress. It doesn't have to be a long message, just a "I'm starting Unit A; just thought you might want to know!"

  3. Your teacher may have special tips and suggestions for the unit you are starting.

  4. Just to say hi – your teacher always enjoys hearing from you!

To contact your teacher, post in the Course Questions Forum, send your teacher an email, or call on the phone if you like. Whatever way you choose, it's always a good idea to get in touch with your teacher – make sure you do it frequently.