Chemical & Physical Changes

Master chemical and physical changes! This worksheet helps 8th graders identify properties and classify changes in matter.

Chemical Physical Properties Physical Property: observed with senses; determined without destroying matterChemical Property: Indicates how a substance reacts with something else; matter will be changed into a new substance after the reaction Sort the items below as either a chemical or physical property Chemical Property flammability (burns) reacts with acid supports combustion (fire) reacts with water reacts with air Physical Property blue color density solubility (dissolves) sour taste melting point boiling point luster odor Chemical Physical Changes Physical Change: a change in size, shape or state; no new substance is formedChemical Change: a change in the physical and chemical properties; a new substance is formed Chemical Change Ag (Silver) tarnishes Baking soda reacts to vinegar Fe (Iron) rusts Milk sours Wood rots Food is digested Physical Change NaCl (table salt) dissolves in water An apple is cut Heat changes H2O to steam Alcohol evaporates Ice melts Sugar dissolves in water Grass grows A tire is inflated Paper towel absorbs water Can you recognize the chemical and physical changes that happen all around us? If you change the way something looks, but haven't made a new substance, a physical change has occurred. If the substance has been changed into another substance, a chemical change has occurred. Classify each of the examples below as either chemical or physical changes but dragging them to the appropriate column. Chemical Change Two chemicals are mixed together and a gas is produced A bicycle changes color as it rusts Two substances are mixed and light is produced A piece of ice melts and reacts with Sodium A marshmallow is toasted over a campfire Physical Change An ice cube is placed in the sun. Later there is a puddle of water. Later still the puddle is gone. A solid is crushed to a powder Mixing salt and pepper Chocolate syrup is dissolved in milk A marshmallow is cut in half Type either true or false for each of the scenarios below. 1) Changing the size and shapes of pieces of wood would be a chemical change.False2) In a physical change, the makeup of matter is changed.False3) Evaporation is a physical change.True4) Evaporation occurs when liquid water changes into a gas. This is an example of a physical change.True5) Burning wood is a physical change.False6) Combining hydrogen and oxygen to make water is a physical change.False7) Sand being washed out to sea from the beach is a chemical change.False8) Breaking up concrete is a physical changeTrue9) When ice cream melts, a chemical change occurs.False10) Acid rain damaging a marble statue is a physical change.False