1-2 Organizing Matter GO 1 Investigate materials, and describe them in terms of their physical and chemical properties.

Guided Question Why is it important to understand the physical and chemical properties of different Substances?

What is Matter?? This is any substance that has a Mass and takes up Space!

Section Organizing Matter What are the states of matter? What determines what state something is? It depends on its _Temperature!

States of Matter solid - the particles are packed so closely together that they only vibrate in place; holds their own form. Liquid - the particles are touching but can flow past each other; takes the shape of the container gas - the particles are separated by large spaces and move Freely; also takes the shape of container

Plasma?? Never heard of plasma? Plasma is the 4rth state of matter. All the electrons have come loose from their respective molecules and atoms. Plasma results when a large amount of energy is added to a gas. Examples: Found in lightning, neon signs, and the Stars.

STATES OF MATTER

Classifications of Matter

Classification of Matter Pure Substances: –Are made up of only one kind of matter –Have a unique set of properties that are different than any other type of matter ELEMENT - cannot be broken down into any simpler substance –Organized into the periodic table

Pure Substances COMPOUND – created when two or more elements combine CHEMICALLY in fixed proportions

MIXTURES A combination of pure substances that have NOT chemically combined to form a compound! –Four types of mixtures Mechanical Mixture Solutions Suspensions Colloid

Mechanical Mixtures (Heterogeneous) In this substance if we looked at it we would be able to see the distinct substances that make it up. All different properties of the substance are visible

SOLUTIONS (Homogeneous) One substance (A) is dissolved into another (B) creating a substance that looks like one substance! –Sugar in hot coffee –Oxygen in the air –Sterling Silver (2 metals mixed) Called an aqueous solution if dissolved in water! –Vinegar (acetic acid in water) –Pop (carbon dioxide in water)

SUSPENSIONS Cloudy mixture with tiny particles of one substance held within another These Particles can be separated when the mixture is poured through filter paper

COLLOIDS Are cloudy mixtures where the particles are so small that they cannot be easily separated from each other! Examples: –Milk –Ketchup –Gels

Physical Properties Properties – are characteristics that can be used to describe a substance. Physical Property – describes the physical appearance and composition of a substance Chemical Property – describes how a substance interacts with other substances, such as acids –Can only be observed when a chemical reaction takes place

Physical Properties of Matter This describes the appearance of a substance: –State at room temperature (Solid/ Liquid/Gas) –Melting point –Boiling point –Hardness ( ability to be scratched) –Malleability ( can it be rolled into sheets or pounded flat?) –Ductility (can it be stretched into a wire ?) –Solubility ( can it be dissolved into another?) –Density (a given weight in a given volume) –Conductivity (can it conduct electricity or heat?)

Chemical Properties of Matter This describes how a substance reacts with other substances: –Reaction with an acid(s) –Ability to burn –Behaviour in air –Reactions to heat –Behaviour in air –Toxic –Explosive

Physical Property shape/texture colour state (room temp) hardness melting/boiling point odor magnetism density conductivity malleability ductility Chemical Property change in odor colour change temp change flammability reactivity new substances To sum up….

Changes in Matter Physical Changes A substance changes in form but not in chemical composition. No new substance is formed. A change in state.  eg. ice melting

Chemical Change A new substance is formed. Is difficult or impossible to reverse.  eg. burning paper, leaves turning colour

Evidence of a Chemical Change The starting material is used up Change in colour Change in temperature Change is smell Gas is produced (bubbles) A precipitate is formed (a new solid) A material with new properties is produced The change is difficult to reverse

Problem 1 What is a physical change? List the physical changes that occur when one makes cheese. Ans: Physical changes include: 1. Dissolving of salt in water 2. Evaporation of water from solution 3. Stirring to mix

Problem 2 What is a chemical change? List the chemical changes that occur when one makes cheese. Ans: changes include: 1. lactic acid bacteria convert the sugar in milk (lactose) to lactic acid 2. special bacteria ferment the remaining lactose and produce carbon dioxide bubbles in the cheese.