Unit 2 - Law of Conservation of Mass

Burning

Chemical Change

Spoiling Milk

Chemical change

Breaking a stick

Physical Change

Freezing

Physical change

Melting

Physical Change

Sublimation

Physical Change

Condensation

Physical Change

Digestion

Chemical Change

Evaporation

Physical Change

chemicals changing colors

chemical change

Leaves Changing Colors In The Fall

Chemical change

Crushing

Physical change

Chopping, Cutting, Carving

Physical change

Rusting

Chemical Change

Tarnishing

Chemical Change

Baking a Cake

Chemical Change

Braiding Hair

Physical Change

Mixing Vinegar and Baking Soda

Chemical Change

Painting your fingernails

Physical Change

Cooking scrambled eggs

Chemical Change

A change in matter that doesn't create a new substance; only the appearance changes

Physical Change

A change in matter that creates a new substance by rearranging atoms.

Chemical Change

Glow Stick Glowing

Chemical Change

Mowing the grass

Physical Change

Boiling water

Physical Change

Photosynthesis

Chemical Change

Folding laundry

Physical Change

Fireworks

Chemical Change

Tearing paper

Physical Change

Making Kool-aid

Physical Change

salt dissolving in water

Physical change

Ice cream melting

physical change

Blending a smoothie

Physical change

rotting food

chemical change

Clouds forming (condensation)

Physical Change

Coefficient

A number in front of a chemical formula in an equation that indicates how many molecules of each reactant and product are involved in a reaction.

Subscript

A number in a chemical formula that tells the number of atoms in a molecule or the ratio of elements in a compound

arrow

yields or produces; indicates a chemical reaction

chemical formula

A combination of chemical symbols and numbers to represent a substance

Chemical equation

a way to describe a chemical reaction using chemical formulas and other symbols

Reactants

A starting material in a chemical reaction

Products

Ending materials in a chemical reaction.

precipitate

A solid that forms from a solution during a chemical reaction.

physical change

A change in a substance that does not change its identity

chemical change

A change in matter that produces one or more new substances

Evidence for a chemical change

production of gas (bubbles), formation of a precipitate, unexpected temperature change, color change, fire, a new product.

open system

A system in which matter can enter from or escape to the surroundings.

closed system

A system in which no matter is allowed to enter or leave

Law of Conservation of Mass

Matter is not created nor destroyed in any chemical or physical change

Solution

A solution is basically two substances

that are evenly mixed together. One

dissolves into the other.

Suspension

A mixture that has a variety of particle sizes in it that will settle on the bottom when not mixed.

Colloid

A mixture that has intermediate sized particles that don't settle at the bottom and scatter light like.

Mixture

A physical combination of two or more substances.

Solute

The substance that gets dissolved in a solution like sugar or salt.

Solvent

The substance that does the dissolving in a solution, commonly water.

Soluble

The substance is able to dissolve in the solution. It appears to have disappeared but it is still there.

Insoluble

The substance cannot be dissolved in the solution. You can still see it.

homogeneous mixture

A mixture in which substances are evenly distributed throughout the mixture

heterogeneous mixture

A mixture in which different materials can be distinguished easily

product

a substance that forms in a chemical reaction

Reactant

A chemical substance that is present at the start of a chemical reaction

Coefficient

A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction.

Subscript

A number in a chemical formula that tells the number of atoms in a molecule or the ratio of elements in a compound