Chemistry 1/2 Lincoln East Course Discussion Notes - Chapter 1 Reading Assignment Ch 1! 1. Read Ch.1 pg 3-22 and while reading, start a science

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1 Chemistry 1/2 Lincoln East Course Discussion Notes - Chapter 1 Reading Assignment Ch 1! 1. Read Ch.1 pg 3-22 and while reading, start a science vocabulary table that includes all terms in bold face type and all terms you are unfamiliar with or unsure of. Your vocabulary table needs to include three things: 1. The term 2. The definition 3. A picture of what the term means to you. 2. Why are you studying chemistry? Where or how can you use the scientific method on a regular basis (besides science class)? Notes: I. Science The knowledge covering general truth or the operation of general laws especially as obtained and tested through the scientific method. A. Scientific Method - A guideline used to pursue answers to many questions or scientific truth. 1. Observation - A description of the physical world a. Qualitative- a description of the a quality or physical nature b. Quantitative- a description of quantity or numerical assessment 2. Interpretation An explanation based on observations. Based on personal bias (how we think & what we know). 3. Hypothesis- Educated Guess - A tentative explanation based on observations and interpretations that attempts to predict future events. a. Commonly in If/then format. 4. Experiment- A format for testing a hypothesis a. Experimental variable- What is being tested b. Experimental group- Who is being tested c. Control- variables or groups that are not being directly tested but used as comparison. In a control group, subjects are exposed to all the same conditions as the experimental group except they are not exposed to the experimental variable. d. Data- measurements or observations that are used to arrive at a conclusion based on the hypothesis e. Study- an examination of a system in which variables cannot be controlled or manipulated. 1. A study can be easily misinterpreted, so care must be taken when analyzing the results. 5. Conclusion- A statement made to either accept or reject the hypothesis a. Theory- a statement that explains the certain results of a hypothesis b. Law- a theory/hypothesis that concisely explains a set of observations and/or experimental data, which cannot be refuted. Scientific Method, here is a slide show: Assignment 1: Ch. 1 Review Questions. p 25. #s: 16, 19, 23, 25, 30, 33, & 35.

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3 C.1 Practice Quiz: Course Discussion Notes - Chapter 2 Reading Assignment Ch 2! 1. Read Ch. 2 pg and while reading, continue building your science vocabulary table that includes all terms in bold face type and all terms you are unfamiliar with or unsure of. Your vocabulary table needs to include three things: 1. The term 2. The definition 3. A picture of what the term means to you. 2. On page 46, Organize the Concept Map into a form that correctly connects the concepts. Notes: I. Chemistry A. What is Chemistry? 1. The study of the composition, structure and properties of matter and the reactions by which matter may be formed or converted into other forms. B. Classification of Matter 1. Matter - an object that has mass and takes up space (volume) a. Mixture- Two or more kinds of matter that can be separated by physical means. 1. Techniques for physical separations- filtration, straining/sifting, magnetism, & distillation b. Types of mixtures 1. Heterogeneous mixture - non-uniform distribution of matter 2. Homogeneous mixture uniform distribution -Solution- another name for a homogeneous mixture 2. Pure Substance- matter that cannot be separated by physical processes a. Element- cannot be broken down into simpler forms of matter 1. chemical symbols- shorthand representation of the elements 2. Groupings of symbols (a way to help you learn symbols) i. symbols that don t match elemental names: ( Na, K, Fe, Cu, Ag, Sn, Sb, W, Au, Hg, Pb) ii. symbols with single letters that match the elemental names: (H, B, C, N, O, F, P, S, Y, I, U ) iii. symbols with 2 letter the match the elemental names: (Li, Be, Cl, Br, Ba, Pt, etc.) b. Compound- pure substances that can be broken down into simpler forms only by chemical processes. 1. chemical formula- a group of chemical symbols representing a compound i. Sodium chloride (salt)- NaCl (1 sodium atom and 1 chlorine atom)

4 ii. Carbon dioxide CO 2 (1 carbon atom and 2 oxygen atoms) C. Properties of Matter 1. Physical Properties- characteristics of matter that can be measured or observed without changing the composition of the matter. a. Intensive properties- mass independent properties. Examples include: color, shape, composition, shape, taste, smell, etc. 1. Temperature- the average heat energy (kinetic) in a substance i. Temperature Scales- 1. Fahrenheit Scale- (32 o 212 o ) degrees 2. Celsius Scale- (0o-100o) degrees ** Fahrenheit and Celsius are standardized by the melting and boiling points of pure water at a certain atmospheric pressure. 3. Kelvin Scale ** absolute zero- point where no heat energy exists within in an object** Conversion Equations: Tc = 5/9(Tf-32) Used to convert a temperature in Fahrenheit to Celsius! Tf = 9/5Tc + 32 Used to convert a temperature in Celsius to Fahrenheit! Tk = Tc Used to convert a temperature in Celsius to Kelvin! Tc = Tk Used to convert a temperature in Kelvin to Celsius! Practice and check your temperature conversion answers here: html Is there a temperature where the Celsius and Fahrenheit temperatures are numerically the same? Answer: Density (intensive properties cont.)- mass per unit volume- apparent heaviness **density of water = 1.0 g/cm 4 o C a. Density = Mass/Volume

5 water Practice and check your density conversion answers here: 3. Specific gravity- ratio of density of matter to density of ** specific gravity has no units. Go here for a long list of specific gravities on many materials: a. Specific Gravity = Density of Material/Density of Water b. Extensive properties = mass dependent properties 1. Heat (Q)- the total amount of heat energy (kinetic energy) 2. Calorie- amount of heat that increases 1 gram of water by 1 o C. 3. Joule- 1 calories = joule Practice Quiz on extensive and intensive properties: C. States of Matter 1. Solid a. Shape = uniform b. Volume = uniform c. Internal heat = low 2. Liquid a. Shape = variable b. Volume = uniform c. Internal heat = medium 3. Gas a. Shape = variable b. Volume =variable c. Internal heat = high 2. Chemical Properties- characteristics that describe the ability of matter to undergo changes in composition where new substances are formed with new properties. a. Example: flammable/combustible, reacts with acids/bases, decomposes under light/uv (light labile), etc. B. Changes in Properties 1. Physical Changes- A change in physical properties of matter without a change in the chemical composition a. Melting/Freezing = Solid / Liquid conversion b. Evaporation/Condensation = Liquid / Gas conversion c. Sublimation = Solid / Gas conversion 2. Chemical Changes- A change in matter that produces new substances with new properties (chemical reaction) a. Reactants = substances that undergo changes

6 b. Products = new substances that are formed 1. Precipitate- a solid produced from solution during a reaction c. Ten indicators of chemical change 1. Bubbles of gas appear 2. Precipitate forms 3. Change in color 4. Temperature changes 5. Light is emitted 6. Change in volume\ 7. Change in electrical conductivity 8. Change in melting or boiling point 9. Change in smell or taste (not to be performed in lab) 10. Change in chemical or physical properties Assignment 2: Ch. 2 Review Questions. p. 47 #s: 27, 29, 33, 36, 40, 42, 44, & 47

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