Changesinmatter Physical and Chemical Properties Physical and Chemical Changes Observable Features of Chemical Reactions
Physical properties • used to identify substances • used to classify substances • used to determine effective building materials
Examples of physical properties • Elasticity • Hardness • Durability • Texture • Shape • Boiling point • Freezing point • Melting point
Chemical Properties • used to identify substances • used to classify substances • used to determine effective building materials • used to determine materials suitable in different environments
Examples of chemical properties • Flammable • Non-flammable • Reacts with water • Doesn’t react with water • Corrosiveness • Toxicity • Combustibility
Physical change • Physical changes………. • are concerned with states of matter • are concerned with energy • form no new substances • include changes in states of matter • Same beginning & ending materials
Examples ofphysical changes • Crushing a can • Melting an ice cube • Breaking a bottle • Boiling water into steam • Forming clay into a sculpture Physical
Chemical change • Chemical changes………. • happen on a molecular level • make new substances • have indicators that change has taken place • Different beginning & ending materials
Examples ofchemical changes • Burning logs in a fire • Cooking an egg • Rusting an iron pan • Mixing soda with vinegar • Exploding fireworks Chemical
Evidence ofchemical changes • Change in color • Change in odor • Energy given off (light, heat, sound) • Gas given off • Precipitate forms
Reaction typesinvolving heat Exothermic reactions (heat is given off) Endothermic reactions (heat is taken in) Boom! Fizz!
Chemical change rates • Rates are affected by…………. • Heating • Cooling • Stirring • Crushing • Concentration
Conservation of matter • Matter – can’t be created or destroyed • Mass – can’t be created or destroyed
Changes in matter • Matter has physical and chemical properties. • Matter can change physically & chemically. • Energy is involved in the changes. • Chemical reactions have observable features. • Matter is conserved in a chemical reaction.