Chapter 3 Matter – Properties and Changes

Warm-Up Complete the Following Conversion: How many centimeters are in 1 mile? Remember to convert them into the most reduced/simplistic format. Required Information 1 Mile = 5280 Ft. 1 Ft. = 12 Inches 1 Inch = 2.54 cm.

Warm-Up Complete the Following Conversion: How many centimeters are in 10 miles? Remember to convert them into the most reduced/simplistic format. 10 Miles x 5280 ft x 12 inches x 2.54 cm = 1,609,344 1 Mile 1 Ft. 1 Inch *Put into Rounded Scientific Notation* 1.61 x 106

Substances What is matter? Substance: Anything that has mass and takes up space Substance: Matter that has a uniform and unchanging composition AKA “Pure Substance” NOT a mixture Example: both H2O (dihydrogen monoxide) and Na2 (Table Salt) are both considered Substances. H20+Na2 = Salt Water is NOT a substance, but is a mixture.

Physical Properties of Matter Physical Property: Any property that can be observed and/or measured without changing the physical composition of the sample. Common Physical Properties: Density Color Odor Taste Hardness Melting Point Boiling Point

Physical Properties and Matter, Cont. Extensive Properties Depends on the amount of substance present Mass, volume and length Intensive Properties Independent of the amount of substance present Density

Quick Write What is the difference between intensive and extensive properties? What is substance? What is the difference between a substance and a compound?

Quick Write What is the difference between intensive and extensive properties? Intensive properties don’t depend on the amount of substance, as they stay they same. Extensive properties depend on the amount of the substance. What is substance? A pure substance, that doesn’t have any mixtures, that remains the same wherever the sample is taken.

Properties of Matter Chemical Properties Observations of Matter The ability/inability of a substance to combine with or change into one or more other substances Iron turns to rust when combined with air When there is NO chemical change Observations of Matter Observing and classifying physical vs. chemical properties of matter May change depending on the environmental conditions Think water, which changes state with temperature

States of Matter Vapor: States of Matter Solid Liquid Gas The different physical forms which matter can take. Solid Has a definite shape and volume. Molecules are tightly packed and when heated only slightly expands. Liquid Matter that flows and has constant volume. Will take the shape of its container. Molecules/particles are not rigidly held in place, less tightly packed and expands when heated. Gas Matter that flows to conform to the shape of its container and will fill the entire volume of the container. Gasses are easily compressed, as their molecules are so widely spread. Vapor: The gaseous state of a substance that is solid or liquid at room temperature.

Changes in Matter Physical Changes Chemical Changes Altering a substance without changing its composition Cutting Paper Breaking a Crystal Cutting Flowers Sawing Wood Chemical Changes Altering a substance which changes it into a new substance AKA chemical reaction Rusting Iron Burning wood Terms related to chemical changes: rust, oxidize, corrode, tarnish, ferment, burn, rot

Massproducts = Massreactants Conservation of Mass Law of Conservation of Mass Mass is neither created nor destroyed during a chemical reaction – instead, it is conserved. ALL mass within a reaction, both the products and reactants, must remain the same. Massproducts = Massreactants

Conservation of Mass Practice If 50 grams of sodium reacts with chlorine to form 126 grams of salt. How many grams of chlorine reacted? If 20 grams of aluminum reacts with 200 grams of bromide to form aluminum bromide, and no aluminum is left after the reaction, but 23 grams of bromine remained unreacted. How any grams of aluminum bromide were formed? If 178.8 g of water is separated into hydrogen and oxygen gas, and the hydrogen gas has a mass of 20.0 g. What is the mass of the oxygen gas produced?

Conservation of Mass Practice, Answers If 50 grams of sodium reacts with chlorine to form 126 grams of salt. How many grams of chlorine reacted? Massproducts = Massreactants Masssodium + Masschlorine = Masssalt 50 grams + Masschlorine = 126 grams Masschlorine = 76 grams If 20 grams of aluminum reacts with 200 grams of bromide to form aluminum bromide, and no aluminum is left after the reaction, but 23 grams of bromine remained unreacted. How any grams of aluminum bromide were formed? If 178.8 g of water is separated into hydrogen and oxygen gas, and the hydrogen gas has a mass of 20.0 g. What is the mass of the oxygen gas produced?

Conservation of Mass Practice, Answers If 50 grams of sodium reacts with chlorine to form 126 grams of salt. How many grams of chlorine reacted? If 20 grams of aluminum reacts with 200 grams of bromide to form aluminum bromide, and no aluminum is left after the reaction, but 23 grams of bromine remained unreacted. How any grams of aluminum bromide were formed? Massproducts = Massreactants Massaluminum + Massbromide = Massaluminumbromide 20+ (200-23) = Massaluminumbromide Massaluminumbromide = 197 grams Massbromide = 23 grams If 178.8 g of water is separated into hydrogen and oxygen gas, and the hydrogen gas has a mass of 20.0 g. What is the mass of the oxygen gas produced?

Conservation of Mass Practice, Answers If 50 grams of sodium reacts with chlorine to form 126 grams of salt. How many grams of chlorine reacted? If 20 grams of aluminum reacts with 200 grams of bromide to form aluminum bromide, and no aluminum is left after the reaction, but 23 grams of bromine remained unreacted. How any grams of aluminum bromide were formed? If 178.8 g of water is separated into hydrogen and oxygen gas, and the hydrogen gas has a mass of 20.0 g. What is the mass of the oxygen gas produced? Massproducts = Massreactants Masswater = Masshydrogengas + Massoxygengas 178.8 grams = 20.0 grams + Massoxygengas Massoxygengas = 158.8 grams

Elements and Compounds Pure substance that cannot be separated into simpler substances by any means, including physical or chemical These are the elements on the periodic table Dimitri Medeleev Organized the periodic table into the rows and columns format that is used today He organized the table into rows called “periods” and columns called “groups” Traits repeat from period to period, which is why the table is called periodic Groups have similar physical and chemical characteristics

The Periodic Table Groups Periods

Compounds A chemical combination of two or more elements Can be broken down into simpler substances, the basic elements Examples Na + Cl = NaCl (Sodium Chloride) N + H3 = NH3 (Ammonia) C12H22O11 (Sucrose)

Mixtures Pure Substances Matter Compounds Heterogeneous Mixtures Homogenous Mixtures Pure Substances Elements Compounds Physical Changes Chemical Changes

Law of Definite Proportions The elements comprising a compound combine in definite proportions by mass percent by mass (%) = mass of element x 100 mass of compound

Law of Definite Proportions Example Problems There are 200 grams of Ba(NO3)2 Ba = 50 grams N = 70 grams 0 = 80 grams 50 g Ba / 200 g Ba(NO3)2 x 100 = 25% Ba 70 g N / 200 g Ba(NO3)2 x 100 = 35% N 80 g O / 200 g Ba(NO3)2 x 100 = 40% O

Law of Multiple Proportions When compounds of different elements are formed, they aren’t exactly identical. They might have different amounts of each element, in relative comparison to another. The law of multiple proportions creates a mass ratio for different elements in similar compounds Mass Ratio Compound I Mass Ration Compound II

Analysis Data of Two Nitrogen Compounds (NO) Finding Mass Ratios Analysis Data of Two Nitrogen Compounds (NO) Compound % N % O Mass of Nitrogen (N) in 100.0 g of Compound Mass of Nitrogen (O) in 100.0 g of Compound Mass Ratio (Mass N / Mass O) I 42.80 57.2 0.74 g N / 1 g O II 56.7 43.6 1.3 g N/ 1 g O Mass Ratio Compound I = 0.74 g N/ 1 g O = .57 Mass Ratio Compound II 1.3 g N/ 1 g O Final Ratio: .57 : 1

Practice Problems Complete the following problems on page 83 of the textbook. Please show all your work. You should complete these within your lab binder. 61 66 67 69