Matter & Change Copy the following essential question at the top of your page EQ: What is the difference between a physical and chemical change of matter?

What is matter? Anything with mass and volume Mass: Mass: the amount of matter in an object – Mass is related to weight, but not exactly weight – Weight depends on what planet you’re on – In chemistry, mass is measured in grams Volume: Volume: – the amount of space an object takes up

What are physical properties of matter? Physical properties are characteristics that can be observed or measured without changing the chemical formula of the substance Mass and volume are physical properties What are some physical properties of ice?

More examples of a physical properties of matter…. Viscosity: A fluid’s resistance to flow Color Density: the amount of mass in a given volume – A box filled with marbles is more dense than a box filled with air – Density = mass/volume

VOCABULARY Intensive Property Intensive Property – DOES NOT DEPEND on the system’s size or the amount of material in the system Ex: Density and Color Ex: Density and Color Extensive Property Extensive Property – DEPENDS on the system’s size or the amount of material in the system Ex. Mass and Volume

What are chemical properties of matter? A chemical property is the ability of something to react with or change into a different substance Reactivity is a chemical property For example, magnesium is flammable. When it burns, it turns into magnesium oxide. Flammability is a chemical property.

Physical Change vs Chemical Change Just as we’ve seen that matter can have physical and chemical properties, matter can change in a physical way or a chemical way.

What is a physical change? A change that doesn’t affect what the substance is. No change in chemical formula. For example, ice is frozen H 2 O. If you melt it, you still have H 2 O. It’s a liquid now, but you haven’t changed the formula or identity. This is referred to as a phase change.

Examples of physical changes…. All phase changes are physical changes: – boiling, melting, evaporating, freezing Other physical changes – Tearing – Cutting – Breaking – Etc.

What is a chemical change? A chemical change is a chemical reaction: the chemical formula changes and a new substance is formed! For example: Water reacts with sodium and turns into sodium hydroxide: H 2 O + Na  NaOH + H 2 The substances you start with (on the left side of the arrow) are the reactants. The substances that result (on the right side of the arrow) are the products.

Signs of a chemical change… Burning Forming a precipitate – Precipitate: formation of a solid from liquids Rusting Releases gas Etc.

Physical/Chemical Change Activity