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1.2 Investigating Matter. Objectives. By the end of the lesson you should be able to: Describe matter using physical properties Use the KMT to describe changes of state. 1.2 Investigating Matter. Matter is anything that has mass and volume
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Objectives By the end of the lesson you should be able to: • Describe matter using physical properties • Use the KMT to describe changes of state
1.2 Investigating Matter • Matter is anything that has mass and volume • Mass: amount of matter in a substance, often measured in grams (g) • Volume: amount of space a substance or object occupies (L)
Describing Matter • Physical Properties: characteristics that can be observed or measured • Qualitative: described (descriptive words – think QUALity) • Quantitative: measured numerically (numbers – think QUANTity)
KMT: Kinetic Molecular Theory • Kinetic Energy: the energy of motion • Kinetic Molecular Theory: explains what happens to matter as the energy in the particles changes
KMT 1. All matter is made up of very small particles 2. There is empty space between particles 3. Particles are constantly moving • Particles of a solid are so tightly packed together that they cannot move around freely. They can only vibrate • Particles of a liquid are farther apart, they can move by sliding past each other • Particles of a gas are very far apart, they move around quickly 4. Energy makes particles move. The more energy particles have, the faster they can move and the farther apart they can get
Changes of State: Energy Levels and Temperature? Gas Solid Liquid Condensation Deposition Evaporation Sublimation Melting Solidification
KMT and Changes of State • When you have a substance in a solid state, we say it has low kinetic energy • When you have a substance in a liquid state, we say it has an increased level of kinetic energy • When you have a substance in a gaseous state, we say it has high kinetic energy
KMT • So when we talk about Kinetic energy, what are we specifically talking about? • We are talking about the energy level in the particles that make up your substance and how fast they are moving
Types of Changes Chemical Changes • A change in matter that results in a new substance • HINTS: explosions, colour changes when heated Physical Changes • A change that results in a change of appearance but no new substance • HINTS: state changes
Types of Changes • Physical Change – a change in matter in which no new substance is produced. • Examples: Popping a balloon, boiling water, breaking glass • Chemical Change – a change in matter in which one or more new substances are produced. • Example: Rust on a car, burning a match
Chemical Change • A chemical change is a change in matter that occurs when substances combine to form new substances • Eg. Fireworks exploding, gases form from the solids in the fireworks
Chemical Change • Designers who make fireworks know that certain substances will change color when they heated. • Sparklers glow bright white because of magnesium. • Magnesium is often added to these fireworks
Types of Changes Ways to Identify Chemical Changes: • Hard to reverse • Something new is produced • Heat and light may be given off • Bubbles of gas may be given off • Solid materials (precipitate) may form in a liquid • New colour may appear
Pure Substances Can be either elements or compounds • Elements: cannot be broken down into simpler substances • Compounds : are two or more elements combined
Your Turn! • Activity Time: Describing Matter Lab!