Natural Sciences - Term 1 - Week 8

Matter is anything that has mass and takes up space. Everything around us is made of matter, including solids, liquids, and gases. For example, a rock is a solid, water is a liquid, and air is a gas. Understanding matter helps us learn about the world and how different substances interact.

A mixture is made up of two or more substances that are combined but not chemically bonded. This means that each substance in a mixture retains its own properties. For instance, when you mix sand and salt, you can still see the individual grains of sand and salt. Mixtures can be homogeneous, where the components are evenly distributed, or heterogeneous, where the components are easily distinguishable.

Let's look at some examples. If we take a glass of orange juice, it is a mixture because it contains water, sugar, and orange pulp. On the other hand, a cube of ice is a pure substance because it is made entirely of water in solid form. Discuss with your partner whether the following items are matter or mixtures: a bowl of fruit salad, a bottle of vinegar, and a piece of chalk.

In groups, students will classify a set of items into pure substances and mixtures. Each group will receive a collection of materials such as sugar, sand, oil, and marbles. They will discuss and decide which items are pure substances and which are mixtures. Afterward, each group will share their classifications with the class, explaining their reasoning.

Students will create their own mixture using household items (e.g., rice, beans, pasta, or small toys). They will document the process by writing a short description of the items used, how they mixed them, and what type of mixture it is (homogeneous or heterogeneous). Finally, they will present their mixtures to the class and explain their findings.

• Anything that has mass and takes up space
• Only solids and liquids
• Only gases
• Only things we can see

Answer: Anything that has mass and takes up space

Matter includes all substances that have mass and occupy space, including solids, liquids, and gases.

• Water
• Salt
• Air
• Sand and salt

Answer: Sand and salt

Sand and salt are combined but retain their individual properties, making them a mixture.

Answer: Saltwater

Saltwater is a homogeneous mixture because the salt is evenly dissolved in the water.

• A mixture where components are evenly distributed
• A mixture where components are easily distinguishable
• A pure substance
• A mixture that cannot be separated

Answer: A mixture where components are easily distinguishable

In a heterogeneous mixture, the different substances can be seen and separated easily.

Answer: They retain their individual properties.

In a mixture, each substance maintains its own properties, unlike in a chemical reaction.

• Mass
• Volume
• Color
• Temperature
• Taste

Answer: Taste

While taste can be a characteristic of a substance, it is not a fundamental property of matter like mass, volume, or color.

• Air
• Sugar
• Fruit salad
• Sand

Answer: Sugar

Sugar is a pure substance because it is made up of only one type of molecule.