Chemistry, Chapters 1 & 2 Unit 1: What is Chemistry and Matter?

Unit Objectives  Be able to identify and distinguish between physical and chemical properties.  Be able to use the metric system.  Be able to distinguish between physical and chemical changes.  Be able to distinguish between mixtures and pure substances, and will be able to use physical properties to separate parts of a mixture.  Be able to describe matter in terms of energy and particle motion.  Standards 1.1, 1.2, 1.3, 6.4

Key Vocabulary  Chemical reaction  Endothermic reaction  Exothermic reaction  Physical state  Product  Reactant  Chemical/Mechanical property  Chemical/Mechanical change  Density  Allotrope  Precision  Heterogenous/homogenous mixture  Ion  pH  Chemical bond  Energy  Law of conservation of energy  Law of conservation of mass  Potential/kinetic energy  Specific heat  Accuracy

Question of the Day  What is chemistry?

Physical States of Matter  What is matter?  States of Matter  Solid  Liquid  Gas  Plasma  Chemical Reactions  Activation Energy  Reactants and Products  Exothermic and Endothermic reactions

Units of Measurement  What is the difference between qualitative and quantity?  SI Units  What are the basic units for  Length  Mass  Time  Volume  Force  Substance amount  Conversion factors

Properties of Matter What does this graph tell you? Physical Properties and Changes Chemical Properties and Changes Gas, precipitate, heat, light, color change

Basic building block of all Matter  What components make up an atom?  Elements  Molecules  Allotrope  Compounds  Ion  Acid or Base  Organic or Inorganic  Mixtures  Homogenous  Heterogenous

Energy  Types of Energy  Law of Conservation of Energy  Law of Conservation of Mass

Measuring Quantities  Accuracy vs Precision  Significant Figures  Nonzero digits are ALWAYS significant  Zeros between nonzero digits are significant  Zeros in front of nonzero digits AREN’T significant  Zeros at the end and to the right of a decimal are significant  Zeros at the end of a number without a decimal point may or may not be significant…depends on if it was measured or estimated  Multiplcation/division: answer has the same # of sig figs as the measurement with the least # of sig figs  Addition/Subtraction: answer has the same # of digits to the right of the decimal as the measurement with the smallest # of digits to the right of the decimal

Scientific Notation  Value expressed in two parts  Move decimal to right/left so there is only ONE nonzero digit to the left of the decimal  Count number of decimal places decimal has to be moved. This is expressed as the exponent  Addition/Subtraction: all must have the same exponent before + or –  Multiplication: factors are multiplied; exponents added  Division: factors are divided; exponents in denominator is – from exponent in the numerator