Matter

Matter and Particles All matter The state of a substance

The Phases of Matter There are FOUR states of matter: Solid 2. Liquid – 3. Gas – 4. Plasma –

Solid Particles In a solid, the particles are ___________________. They vibrate in place and the attraction between them is _________. This causes the particles to lock together.

Liquid Particles In a liquid, the particles ______________________________ _____________________. This allows the particles to flow around and over each other. Liquids assume _____________________________. Liquids can also be called ________– which means a ____________________________

Gas Particles In a gas, the particles ____________________________ ____________________________ ___________________________. That’s why a gas will spread out in all directions – filling up a balloon, a room, or the atmosphere.

Melting: From Solid to Liquid The temperature at which a solid melts is called its _____________. The melting point is different for different solids. For ice, it is 0oC or 32oF.

Melting and the Particles As you heat a solid, the particles in that solid will begin to move______. _____________________________. Eventually the motion of the particles will become great enough to overcome the attraction that locks the particles together as a solid. When that happens, the solid becomes a liquid because the particles start to flow.

Freezing: From Liquid to Solid The temperature at which a liquid freezes is called its _____________. The freezing point for different solids is different. For water, it is 0oC or 32oF.

Freezing and the Particles If you cool a liquid, the particles will begin to _____________. ____________________________. Eventually the motion of the particles will slow to the point where they cannot overcome the attraction between them. When that happens, the particles will lock together and become a solid.

Vaporization: From Liquid to Gas The temperature at which water changes from a liquid state to a gaseous state is 100oC or 212oF. This is known as its _____________.

Vaporization and the Particles As a substance is heated, its particles begin to _________________. ______________________________. During vaporization, the fastest particles are able to overcome the attraction of the particles around them and break free completely. These escaped particles become a gas (ex: water vapor).

Vaporization vs. Evaporation Vaporization refers to _____________________________ _____________________________. ______________ is a specific type of vaporization which occurs at temperatures below the boiling point of a liquid. So vaporization includes ___________________________.

Vaporization vs. Evaporation Evaporation occurs _________________________, but vaporization could happen _________________________when a liquid is boiling. Think about water evaporating from a puddle vs water boiling in a pot.

Vaporization: Solid to Gas Sublimation This is a result of vapor pressure and temperature relationships. (Examples include dry ice and freeze drying food.)

Condensation: From Gas to Liquid The temperature at which a gas condenses is called its condensation point. For water vapor, it is 100oC or 212oF.

Condensation: From Gas to Liquid If you cool a gas, the particles will begin to ______________. ____________________________. Eventually the motion of the particles will slow to the point where they cannot overcome the attraction between them. When that happens, the particles will lock together and become a liquid.

Physical Properties A physical property of matter Some physical properties are color, odor, mass, volume, magnetism, ability to conduct current, strength, flexibility, hardness, and texture. Ex – Will your books fit into you backpack? You are using the physical property of volume.

Physical Properties Thermal conductivity – State of Matter – Density – Ex. Styrofoam is a poor conductor. State of Matter – (ex: ice, water, water vapor) Density – (ex: Lead is very dense so it is used to make an anchor.)

Physical Properties Solubility – Ductility – Malleability – (ex: Kool-Aid power dissolves is water.) Sometimes you can increase solubility by changing the temperature. Ductility – (ex: Copper is often used to make wiring because it is ductile.) Malleability – (ex: Aluminum can be rolled into sheets to make foil.)

Physical Changes A physical change is Ex. A piece of silver is pounded and molded into a heart-shaped pendent. (it is still silver) Ex. – changing from a liquid to a solid (or any phase change) Ex. – crushing an Aluminum can. It is still aluminum, just the shape has changed. Ex – Sawdust – it is still wood – only in smaller pieces.

Chemical Properties Chemical properties describe matter based on its ____________________________________ ____________________________________ (in the form of a chemical reaction). Chemical changes occur when Ex. – burning wood, tarnishing, and rusting

Chemical Properties Flammability – (wood can burn, but ash and smoke cannot) Reactivity – is the ability of two or more substances to ___________________________________ Chemical reactions involve two main kinds of changes that you can observe – ____________________________________

Physical Properties vs. Chemical Properties A nail will bend – A nail will rust – _____________________ ______________________(iron is reacting with oxygen to make iron oxide - ___________) Alcohol will evaporate – Alcohol will burn – ________________– it is not alcohol any more.

How do I know that a chemical change is taking place? There will be a change is odor, color, heat will be either absorbed or released, the substance will bubble or fizz, light or sound may be given off. Ex.

Changes in Energy As matter changes, it can either absorb or release energy. A change in energy occurs during a chemical reaction. An endothermic reaction Many endothermic reactions occur when heat is constantly added. (Ex: egg frying) In other words…they need energy to keep going.

Changes in Energy An exothermic reaction After an exothermic reaction, the products have less energy than the reactants. (Ex: the burning of fuel) The reaction between fuel and oxygen in an airplane engine releases energy, mostly in the form of heat. The expansion and movement of the gases out of the plane exerts a force that moves the plane forward.

Can physical and chemical changes be reversed? Physical changes are ___________________. You can melt ice and then freeze it again. Chemical changed are _________________. When a firework explodes it would be almost impossible to put the materials back together.