Matter and Measure

 Two main systems  English ◦ Based on arbitrary measurements that have lasted through history ◦ Conversions are harder to remember  Metric ◦ Based on powers of ten ◦ Prefixes determine magnitude of power of ten

 Scientific Community has accepted certain units as base units DimensionUnitSymbol LengthMeterm MassGramg TimeSeconds TemperatureKelvinK AmountMolemol

PrefixPowerSymbol Giga10 9 G Mega10 6 M kilo10 3 k deci10 -1 d centi10 -2 c milli10 -3 m micro10 -6 μ nano10 -9 n pico p

 Digital Displays are recorded as is ◦ Digital Mass Balance, pH meter  Visually Read Scales can always be estimated to smaller increment than marked ◦ Rulers, Thermometers, Graduated Cylinders ◦ Meter stick Example

0m0.4m0.2m0.1m0.3m  Length=??  0.3m0.31m0.314m

 Measure related to the heat of an object  Measured in °Celsius or Kelvin(no degrees)  Conversion

 Amount of matter in a given amount of space  Amount of mass in a given volume

 What is Chemistry? ◦ Study of matter and the changes it undergoes  Branches ◦ Organic ◦ Physical ◦ Analytical ◦ Biochemical ◦ Inorganic

 International Union of Pure and Applied Chemistry  Group that names elements and compounds  Meets every few years

 Anything that has mass and takes up space, volume  Classified into two categories ◦ Substances (Pure) ◦ Mixtures

 Simplest form of matter  Made up of Subatomic Particles  Different atoms have different properties

 Element ◦ simplest form of matter that has a unique set of properties. ◦ arranged into a table, called the periodic table ◦ Can’t be broken down by chemical means ◦ denoted using chemical symbols, O, Cu, Fe  Symbols always have the first letter capitalized  If needed, any additional letters are not capitalized

 Compounds ◦ substance of two or more elements chemically combined in a fixed proportion ◦ Ex. H 2 O, C 6 H 12 O 6 ◦ Can be broken down by chemical means

 Physical blend of two or more substances  Two Types: ◦ Homogeneous ◦ Heterogeneous

 Homogeneous ◦ Composition is uniform throughout ◦ Examples: Air, Olive Oil, Stainless Steel ◦ Solution is a homogeneous mixture ◦ Aqueous Solution is something mixed in water  Heterogeneous ◦ Composition is not uniform throughout ◦ Examples: Salad Dressing, Chicken Noodle Soup

 Differences in physical properties can be used to separate mixtures ◦ Filtration – Separates solids from liquids in heterogeneous mixtures ◦ Distillation – Separates homogeneous liquid mixtures based on different boiling points

◦ Evaporation – evaporate away liquid to leave solid ◦ Chromatography – separation of substances based on polarity

 Solid ◦ Definite shape and volume ◦ Particles are packed tightly together in a regular geometric pattern ◦ (s) used after chemical formulas ◦ Cu (s)

 Liquid ◦ Definite volume, takes shape of container ◦ Particles can slide past each other ◦ ( l ) used after chemical formulas ◦H2O(l)◦H2O(l)

 Gas ◦ Takes shape and volume of container ◦ Particles are spread very far apart ◦ (g) used after chemical formulas ◦ H 2 O (g)

 Dissolved in water  (aq) used after chemical symbols ◦ NaCl (aq)

 Solid  LiquidMelting  Liquid  SolidFreezing  Liquid  GasVaporization  Gas  LiquidCondensation  Solid  GasSublimation  Gas  SolidDeposition  Temperature does NOT change during a phase change

 Physical Property ◦ quality or condition of a substance that can be observed or measured without changing the substance’s composition ◦ Ex: Color, shape, size, mass  Physical Change ◦ some properties change, but the composition remains the same ◦ Can be reversible or irreversible ◦ Ex: melting, freezing, tearing

 Chemical Change ◦ change that produces matter with a different composition than the original matter ◦ Ex. burning, rusting, decomposing, exploding, corroding  Chemical property ◦ property that can only be observed by changing the composition of the substance. ◦ Ex: Reactivity with acids, reactivity with oxygen

 Boiling PointPhysical  Green colorPhysical  ShinyPhysical  ConductivityPhysical  SolubilityPhysical  Reacts with acidChemical  Reacts with O 2 Chemical

 Capacity to do work  Ability to do something  Types: ◦ Chemical ◦ Electrical ◦ Mechanical ◦ Potential ◦ Kinetic

 Exothermic ◦ Process when energy is released or given off ◦ Ex: Burning, freezing  Endothermic ◦ Process when energy is absorbed or taken in ◦ Ex: Melting

 Observation ◦ using five senses to make observations.  Hypothesis ◦ proposed explanation for an observation.  Experiment ◦ procedure used to test a hypothesis.

 Analyze Data ◦ check to see if results support hypothesis.  Theory ◦ well tested explanation for a broad set of observations.  Law ◦ concise statement that summarizes the results of many observations and experiments.

 Law of Conservation of Mass ◦ Mass can not be created or destroyed, only changed into different forms  Law of Conservation of Energy ◦ Energy can not be created or destroyed, only changed into different forms