Matter What is matter PURE SUBSTANCES or MIXTURES
Matter
What is matter? PURE SUBSTANCES or MIXTURES Pure substances ALWAYS HOMOGENEOUS What is the difference between an element and a compound? Element = cannot be broken down any more Compound = composed of 2 or more elements Compounds can ALWAYS be broken down into simpler substances, elements cannot
How are compounds broken down? Cannot be broken down physically We can’t throw table salt (Na. Cl) at the wall and break it down into its individual components Must be done chemically Produce matter with a different composition than the original matter
Distinguishing Between a Substance and a Mixture? Easy Rule of Thumb If the composition of a material is fixed (meaning it cannot change) Substance If the composition of a material may vary (meaning it can change) Mixture
Examples Milk Mixture (low-fat, skim, whole, 2% etc. ) Diamond Substance (carbon doesn’t change) Gasoline Mixture (premium, regular, and unleaded) Stainless Steel Mixture (carbon and iron together) Silver Substance (an element, doesn’t change)
Mixtures What is a mixture? A physical blend of two or more components Can be classified in TWO different ways Heterogeneous mixtures Homogeneous mixtures
Heterogeneous Mixture What is a heterogeneous mixture? Composition is not uniform throughout the mixture Examples Chicken noodle soup Trail mix Chocolate chip cookies Types of heterogeneous mixtures Colloids Particles are very, very small Suspensions Particles are big; visible to us; don’t settle back down
Homogeneous Mixture What is a homogeneous mixture? The composition is uniform throughout Examples Creamy peanut butter Air Koolaid Types of homogenous mixtures Solutions Just another name for homogenous mixture
Mixtures in General What is a phase? Any part of a sample with uniform composition and properties Homogeneous mixtures Have only 1 phase all the time Heterogeneous mixtures Consists of 2 or more phases What is a coarse mixture? Mixture where you can see all the particles clearly There is no blending of the ingredients like in a suspension Examples Fruit salad
How Do We Separate Mixtures? Two ways of separating mixtures Filtration Separating a solid from a liquid Straining spaghetti Distillation Separating small particles from a mixture Boil the mixture and collect the gas Making Distilled water
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