Classifying Matter: Elements and Compounds
Matter Definition: – It has mass or weight – Takes up space (volume) Examples- anything; car, water, you, cat, dog, table, chair, air, food…..
Elements Pure substance that cannot be separated into simpler substances by physical means (or methods).
Elements Examples: Oxygen, carbon, iron, gold, sulfur, nitrogen, hydrogen, calcium, chlorine, copper, sodium Anything on the Periodic Table
Atoms The smallest unit of an element that maintains (or keeps) the properties of that element.
Molecules Composed of 2 or more elements that are joined by chemical bonds. – Elements can be the same. Examples: H 2, O 2, N 2 – Elements can be different. Examples: H 2 O, C 6 H 12 O 6
Compounds Pure substance composed of two or more different elements that are chemically combined. Made of elements in a specific ratio that is always the same – Has a chemical formula. Water is H 2 O – it will always have 2 hydrogen atoms and 1 oxygen atom bonded together.
Compound Examples: CompoundFormulaElements combined Table SaltNaClSodium and chlorine Water H 2 OHydrogen and oxygen Carbon dioxide CO 2 Carbon and oxygen Sugar (glucose) C 6 H 12 O 6 Carbon, hydrogen, and oxygen Baking sodaNaHCO 3 Sodium, hydrogen, carbon and oxygen
Compounds (continued) Water can only be separated by chemical methods, not physical methods The physical and chemical properties of a compound are different than the properties of the elements in it – Example: water is H 2 O. Hydrogen and oxygen are gases at room temperature, and they are both flammable. Water is a liquid at room temperature and is not flammable. – Other examples are NaCl (salt), HCl (hydrochloric acid), and C 6 H 12 O 6 (glucose)
Mixtures A combination of two or more pure substances that are not chemically combined. The substances are held together by physical forces, not chemical No chemical change takes place when making a mixture Each item in the mixture retains its properties They can be separated physically (using hands, magnets, strainer, etc.) There are 2 types of mixtures, homogeneous (molecules are evenly mixed ) and heterogeneous (not evenly mixed) Chem4kids.
Mixtures (continued) Examples include salad, your trick-or- treating bag full of candy, salt water, jelly beans (with 2+ flavors) Heterogeneous Homogeneous
Mixtures vs. Compounds
Solutions A mixture that appears to be a single substance - one compound is dissolved in another compound. The solute is the substance being dissolved in another substance. The solvent is the substance in which the solute is being dissolved. Water is considered a universal solvent, which means that more substances can be dissolved in it than any other substance.
Solutions (continued) Examples: lemonade, Kool-Aid, Coke and other soft drinks (water, sugar, CO 2, etc. - they have liquids, gases and solids are dissolved together), and salt water
Can you identify the following? You will be shown a series of photos. Tell if each photo represents an item composed of an element, compound, or mixture. Review: An element contains just one type of atom. A compound contains two or more different atoms joined together. A mixture contains two or more different substances that are only physically joined together, not chemically. – A mixture can contain both elements and compounds. – A solution is a type of mixture where substances are dissolved.
Element, Compound, or Mixture or Solution? Copper
Element, Compound, or Mixture or Solution? Copper
Element, Compound, or Mixture or Solution? Jelly Beans
Element, Compound, or Mixture or Solution? Jelly Beans
Element, Compound, or Mixture or Solution? Table Sugar
Element, Compound, or Mixture or Solution? Table Sugar
Element, Compound, or Mixture or Solution? Diamond
Element, Compound, or Mixture or Solution? Diamond
Element, Compound, or Mixture or Solution? Tea
Element, Compound, or Mixture or Solution? Tea
Element, Compound, or Mixture or Soltuion? Salt
Element, Compound, or Mixture or Solution? Salt
Element, Compound, or Mixture or Solution? Neon Gas
Element, Compound, or Mixture or Solution? Neon Gas
Element, Compound, or Mixture or Solution? Salad
Element, Compound, or Mixture or Solution? Salad
Element, Compound, or Mixture or Solution? Pure Water
Element, Compound, or Mixture or Solution? Pure Water
Element, Compound, or Mixture or Solution? Aluminum
Element, Compound, or Mixture or Solution? Aluminum
Element, Compound, or Mixture or Solution? Lemonade
Element, Compound, or Mixture or Solution? Lemonade
Element, Compound, or Mixture or Solution? Silver
Element, Compound, or Mixture or Solution? Silver
Element, Compound, or Mixture or Solution? Sand
Element, Compound, or Mixture or Solution? Sand
Notes Detailed notes are located at: -compounds-mixtures-notes-isn.pdf Flow Chart: chart-isn.pdf