Chemistry UPV

• Matter, Energy, and Measurement
• Chemistry


  The study of matter, its properties, and the changes that matter undergoes
• Matter


  The physical material of the universe; Anything that has mass and occupies space
• Property


  Any characteristic that allows us to recognize a particular type of matter and to distinguish it from other types
• Matter is comprised of combinations of only about 100 substances called elements
• Atom


  Almost infinitesimally small building blocks of matter where each element is composed of a unique kind of atom
• Molecule


  Two or more atoms joined in specific shapes
• States of Matter

  • Gas (vapor)
  • Liquid
  • Solid
• Gas (vapor)


  Has no fixed volume or shape; can be compressed or expand to occupy a different volume
• Liquid


  Has a distinct volume independent of its container, assumes the shape of the portion of the container it occupies, and is not compressible to any appreciable extent
• Solid


  Has both a definite shape and a definite volume and is not compressible to any appreciable extent
• Pure substance


  Matter that has distinct properties and a composition that does not vary from sample to sample; Either an element or a compound
• Element


  Substance that cannot be decomposed into simpler substances; Composed of only one kind of atom
• Some Common Elements and Their Symbols

  • Carbon (C)
  • Fluorine (F)
  • Hydrogen (H)
  • Indium (I)
  • Aluminum (Al)
  • Boron (B)
  • Calcium (Ca)
  • Chlorine (Cl)
  • Copper (Cu)
  • Iron (Fe)
  • Lead (Pb)
  • Magnesium (Mg)
  • Mercury (Hg)
  • Nitrogen (N)
  • Potassium (K)
  • Silver (Ag)
  • Sodium (Na)
  • Sulfur (S)
  • Tin (Sn)
  • Zinc (Zn)
• Compound


  Substance composed of two or more elements; Contains two or more kinds of atoms
• Mixture


  Combination of two or more substances in which each substance retains its chemical identity
• Types of Mixtures

  • Homogeneous (one phase, uniform appearance, same properties and composition)
  • Heterogeneous (more than one phase, visibly distinguishable components)
• Solution


  Homogeneous mixture with particle sizes at the molecule or ion level
• Colloid


  Homogeneous mixture with particle sizes that consist of clumps of molecules; Examples are fog and milk
• Suspension


  Mixture with particles large enough to be visible to the naked eye; Examples are blood and aerosol sprays
• Law of constant composition (or the law of definite proportions) - the observation that the elemental composition of a compound is always the same
• Physical property


  Can be observed without changing the identity and composition of the substance
• Chemical property


  Describes the way a substance may change, or react, to form other substances
• Intensive property


  Does not depend on the amount of sample being examined; Examples are density and concentration
• Extensive property


  Depends on the amount of sample; Examples are mass and volume
• Physical change


  Substance changes in physical appearance but not its composition
• Chemical change (chemical reaction)


  Substance is transformed into a chemically different substance
• Separation of Mixtures: Distillation, Filtration, Chromatography
• Energy


  The capacity to do work or transfer heat
• Work


  The energy transferred when a force exerted on an object causes a displacement of that object
• Heat


  The energy used to cause the temperature of an object to increase
• Force


  Any push or pull exerted on an object
• Kinetic Energy


  The energy of motion
• Potential Energy


  The "stored" energy that arises from the attractions and repulsions an object experiences in relation to other objects
• Chemical energy


  Potential energy stored in the arrangements of atoms; Released when bonds between atoms are formed and consumed when bonds between atoms are broken
• The units used for scientific measurements are those of the metric system
• SI Units: Length (meter), Mass (kilogram), Time (second), Amount of substance (mole), Temperature (kelvin), Electric current (ampere), Luminous intensity (candela)
• Temperature


  A physical property that determines the direction of heat flow; Heat always flows spontaneously from a substance at a higher temperature to one at a lower temperature
• Celsius scale


  Originally based on the assignment of 0 °C to the freezing point of water and 100 °C to its boiling point at sea level
• Kelvin scale


  The SI temperature scale, with zero representing absolute zero (the temperature at which all thermal motion ceases)