Properties of Matter PDF

Chapter 15 – Section 2 Properties of Matter Physical Properties Characteristics of a material that can be observed without changing the identity of the substances that make up the material Physical Properties Color Size Shape State...

Chapter 15 – Section 2 Properties of Matter Physical Properties Characteristics of a material that can be observed without changing the identity of the substances that make up the material Physical Properties Color Size Shape State of matter Melting and boiling point Magnetic Ductile Malleable Density Solubility Texture Electrical conductivity Physical Changes A change in size, shape or state of matter The identity of the material – its chemical composition - remains the same. Phase Changes are all Physical Changes Using Physical Properties to Separate Mixtures Distillation A process for separating substances in a mixture by evaporating a liquid and condensing the vapors. Sieving A process for separating substances in a mixture by size.  Chemical Properties Characteristics of a substance that indicate whether or not it can undergo a certain chemical change.  Chemical Properties Flammability Changes in the Does it explode? presence of light Rust? Reacts with oxygen Tarnish? Reacts with water Rot? Decay? Reacts with acid Sour? Inert – not reactive Is it corrosive? Electrolysis – changes when exposed to an electric current. Detecting Chemical Change: - Look for the formation of a new substance Clues: Change in odor/smell foaming /bubbles forming - indcates formation of a gas. Heat / thermal energy given off or absorbed Detecting Chemical Change: Clues: Light and/or sound energy given off Change in color formation of a powder (precipitate) from two solutions During a chemical change, new substances are formed. Chemical Reaction of sodium & chlorine http://www.youtube.com/watch?v=Mx5JJWI2aaw  Law of Conservation of Mass MATTER IS NEITHER CREATED NOR DESTROYED IN A CHEMICAL REACTION The mass of all substances that are present before a chemical change equals the mass of all the substances that remain after the change. The exact same atoms are present before and after the reaction. They are rearranged to form new substances. The mass of all substances that are present before a chemical change equals the mass of all the substances that remain after the change. 1. In the following reaction, 24 g of CH4 react with 96 g of O2 to form 66 g of CO2. How many grams of H2O are formed? CH4 + 2 O2 → CO2 + 2 H2O 54 g of H2O 2. In the following equation, 54.0g of Al react with 409.2 g of ZnCl2 to form 196.2 g of Zn metal. How many grams of AlCl3 are formed? (Do not worry about the numbers in front of the chemical formulas) 2 Al + 3 ZnCl2 → 3 Zn + 2 AlCl3 A chemical reaction produces two products, one with a mass of 34 g and the other with a mass of 39 g. What was the total mass of the reactants? a. 73 g b. 5 g c. 34 g d. 39 g 1. A chemical reaction produces two products, one with a mass of 34 g and the other with a mass of 39 g. What was the total mass of the reactants? Total mass reactants = total mass of products 34 g + 39 g = 73 g Two solutions, one with a mass of 450 g and the other with a mass of 350 g, are mixed. A chemical reaction occurs and 125 g of solid crystals are produced that settle on the bottom of the container. What is the mass of the remaining solution? a. 225 g b. 800 g c. 100 g d. 675 g 2. Two solutions, one with a mass of 450 g and the other with a mass of 350 g, are mixed. A chemical reaction occurs and 125 g of solid crystals are produced that settle on the bottom of the container. What is the mass of the remaining solution? 450 g + 350 g = 125 g + mass solution (450 g + 350 g) - 125 g = mass solution = 675 g Carbon reacts with oxygen to form carbon dioxide according to the following equation: C + O2 → CO2. When 120 g of carbon reacts with oxygen, 440 g of carbon dioxide are formed. How much oxygen reacted with the carbon? a. 560 g b. 320 g c. 440 g d. 120 g Carbon reacts with oxygen to form carbon dioxide according to the following equation: C + O2 → CO2. When 120 g of carbon reacts with oxygen, 440 g of carbon dioxide are formed. How much oxygen reacted with the carbon? 120 g C + ? g oxygen = 440 g CO2 mass oxygen = 440 g - 120 g = 320 g