Matter: Properties, Mixtures and Changes: Grade 5 Study Guide
Everything with mass that takes up space is matter, and it can be described by its properties.
Matter is anything that has mass and takes up space. All matter is made of tiny particles too small to see. In solids the particles are packed closely and vibrate in place; in liquids they slide past one another; in gases they spread out and move freely. Heating makes particles move faster.
Materials are described by their properties: color, hardness, flexibility, conductivity, solubility, magnetism and density. Scientists use these to choose the right material for a job, such as copper for wires and plastic for handles.
States and properties
| State | Shape | Volume | Particles |
|---|---|---|---|
| Solid | fixed | fixed | close together, vibrate |
| Liquid | takes container's shape | fixed | close, slide past each other |
| Gas | takes container's shape | fills the container | far apart, move quickly |
Mixtures and solutions
A mixture contains two or more substances that are not chemically joined and can be separated again. Sand and salt can be separated by dissolving the salt in water, filtering out the sand and evaporating the water. In a solution such as salt in water, the substance dissolves and spreads evenly. Methods of separating mixtures include sieving, filtering, evaporating and using a magnet.
Salt dissolves; sand does not.
Sand stays on the paper.
Water leaves as vapor.
Salt crystals remain.
Conservation of matter
When matter changes state or dissolves, the total amount of matter stays the same. If 100 g of ice melts, you still have 100 g of water. If 5 g of sugar dissolves in 95 g of water, the solution has a mass of 100 g. A physical change (melting, tearing, dissolving) does not make a new substance. A chemical change (burning, rusting, baking) does, and signs include gas bubbles, a color change, light or heat.
Worked example and common misconceptions
Example: Baking soda and vinegar fizz because they make a new gas, carbon dioxide: a chemical change. Common misconceptions: thinking dissolved sugar has disappeared (it is still there), thinking a gas has no mass and thinking all changes can be reversed. Always weigh before and after to test conservation of mass.
Check your understanding: model answers
1. Solid, liquid and gas. 2. Evaporate the water. 3. A physical change.
✨ Key Takeaways
- Matter is made of tiny particles.
- Properties help choose materials.
- A mixture can be separated; a solution looks even.
- Total mass is conserved in a change.
💬 Questions for Discussion & Reflection
- Name the three common states of matter.
- How can you separate salt from water?
- Is melting a physical or chemical change?
Print a science experiment report →