10.1 The Nature of Matter Matter is a term used to describe anything that has mass and takes up space. All the “stuff” around you is matter and you are matter too. Examples: air, plastic, metal, wood, glass, paper and cloth Matter can have many different properties or characteristics, that can be used to identify or classify it.

Greek philosophers Democritus and Leucippus proposed that matter is made of tiny particles called atoms. Atoms were an idea that few believed. The first evidence was called Brownian motion for Robert Brown, who first noticed the jerky motion of tiny particles.

10.1 The Nature of Matter Varying the mass and size of particles that collide can have different effects. Throwing marbles at a tire tube moves the tube smoothly. Throwing the same marbles at a foam cup moves the cup in a jerky way, like Brownian motion.

Some types of matter are substances and some are not Some types of matter are substances and some are not. In chemistry , a substance is a single kind of matter that is pure meaning that it always has a specific makeup or composition. An element is a pure substance that cannot be broken down into other substance by chemical or physical means. All of the matter you are ever likely to experience is made from one or more elements in nature.

10.1 Elements For example, water can be broken down into its elements, hydrogen and oxygen, when energy is added.

An atom is the basic particle from which all elements are made. The scientific theory of atoms explains that all matter is made up of atoms. An atom is the basic particle from which all elements are made. The elements have different properties because their atoms are different. An atom has a positively charged center called a nucleus which contains smaller particles called protons. The nucleus is surrounded by a cloud of negatively charged particles called electrons.

Carbon atoms are different from sodium, aluminum, or oxygen atoms. They have different masses.

Atoms of most elements are able to combine with other atoms. When atoms combine they form a chemical bond. A molecule is a group of two or more atoms joined together by a chemical bond.

10.1 Compounds and elements Compounds are two or more different elements chemically combined in a set ratio. A compound is represented by a chemical formula which shows the elements in the compound and the ratio of atoms.

10.1 Examples of compounds Compounds contain more than one type of atom joined together. When elements form compounds they have properties that are different from those of the elements.

Elements and compounds are substances but most materials are mixtures. A mixture is made of two or more substances that are together in the same place but their atoms are NOT chemically bonded. How many atoms are in this mixture? How many molecules are in this mixture?

Each substance in a mixture keeps its own properties. The parts of a mixture are not combined in a set ratio. Can you distinguish between atoms and molecules in these images?

Homogeneous mixture A homogeneous mixture is a mixture that is so evenly mixed that you can’t see the different parts therefore it is difficult to separate into its different parts. Example: lemonade, air

Heterogeneous mixture A heterogeneous mixture is a mixture in which different samples are not necessarily made up of the same proportions of matter. Example: chicken soup, salad

Ways to separate mixtures Chromatography Distillation Distillation video 2 Magnets Filtration Evaporation

Answer Questions pg. 233 numbers 2,3,5,6

Pure substance and mixtures chart Sample Pure substance or mixture Components of sample Can it be separated by physical means? Possible separation methods A B C D E F