Changing Matter Mind Map
← Changing MatterHow matter can be mixed, separated, or changed into new substances, and why the number and type of atoms (and the mass) stay the same in a closed system.
- atomThe smallest unit of an element that keeps that element’s chemical identity.Every atom of gold is the same kind of atom.
- elementA pure substance made of one kind of atom; chemical reactions cannot break it into simpler substances.Oxygen is an element.
- moleculeA group of two or more atoms held together by chemical bonds.A water molecule has two hydrogen atoms and one oxygen atom.
- compoundA substance made of two or more elements joined together chemically, like water (H₂O).Table salt is a compound of sodium and chlorine.
- mixtureTwo or more substances mixed together but not joined chemically, like trail mix or salt water.Salad is a mixture you can pick apart.
- solutionA mixture where one substance dissolves evenly into another, like sugar in water.Salt water is a solution.
- suspensionA mixture with particles big enough to settle out if it sits, like muddy water.Muddy water is a suspension, so the dirt sinks over time.
- colloidA mixture with tiny particles that stay spread out and do not settle, like milk or fog.Milk is a colloid.
- dissolveTo break apart and spread evenly through a liquid.Sugar will dissolve in warm tea.
- physical changeA change in size, shape, or state that does not make a new substance.Cutting paper is a physical change.
- chemical changeA change that makes a new substance, like burning or rusting.Baking a cake is a chemical change.
- chemical reactionA process in which substances turn into new substances.A chemical reaction made the steel wool rust.
- reactantA substance you start with in a chemical reaction.In the equation, hydrogen and oxygen are the reactants.
- productA new substance that forms in a chemical reaction.Water is the product when hydrogen burns.
- chemical equationA short way to write a chemical reaction using symbols, showing what you start with and what forms.The chemical equation shows two hydrogen molecules and one oxygen molecule forming water.
- conservation of massThe rule that matter is not created or destroyed in a change, so the total mass stays the same.Because of conservation of mass, the sealed bag weighed the same before and after.
- closed systemA system where no matter can get in or out.A sealed jar is a closed system.
- open systemA system where matter can move in and out.An open cup of fizzing soda is an open system, so gas escapes.
- massHow much matter is in an object.We measured the rock’s mass on a balance.
- volumeThe amount of space an object or substance occupies.Mixing alcohol and water gives a volume a little less than the two added together.