Matter Chapter 4

Pure Substances and Mixtures Matter can be divided into two groups: Pure substances: all the particles of a substance are the same Or Mixtures : a sample contains different types of particles

There are two types of pure substances Elements: From the periodic Table, they have only one type of atom Compounds: Specific combinations of atoms that chemically bond together

Elements: Cannot be broken down by ordinary chemical reactions Compounds: : Can be broken down by ordinary chemical reactions

Mixtures Mixtures can be separated into their components by simple physical methods: Filtering, magnets, skimming, distillation

Which is it? Compound Mixture Element

Matter Can Be Classified All matter No Yes Can it be separated by physical method? Pure Substance Mixture Yes Can it be decomposed by chemical process? No Yes No Is it uniform throughout? Compound Element Heterogeneous Homogenous

Properties of Matter Physical Property: A characteristic of a substance that can be observed and measured without changing the identity of the substance. Chemical property: The ability of a substance to react and form a new substance.

What are some Physical Properties? Properties you can see, such as color, shape, hardness, and texture, viscosity, solubility conductivity… Properties that are easily measured, such as mass, volume, density, melting point, boiling point, Density… Which properties are Quantitative; Which are qualitative? Is the ability to be attracted to a magnet a physical property?

State: Is this a physical of a chemical property?

Density Density is a measure of the amount of matter in a certain amount of space. Formula: Density =Mass Volume D=M V

Let’s Try Some Density Problems 1) If the mass of a rock is 500g and its volume is 25cm3, what is its density? 2) If the density of a liquid is 1.2 g/mL, and its volume is 10mL, what is its mass? 3)If Bob’s mass is 80kg and his density is 1.6kg/L, what is his volume?

Chemical Properties Chemical properties describe substances’ ability to change into a different substance. Reactivity with water ,oxygen, acids, other substances. Combustibility Stability, toxicity