Chapter 2 - Small Molecules and the Chemistry of Life

• What is the smallest particle of matter?

  Atom
• What does Dalton's atomic theory state about atoms?

  Atoms are indivisible and cannot be created or destroyed
• Are all atoms of a given element identical?

  No, they can have different masses
• What is a compound made of?

  Two or more different types of atoms
• How are compounds represented in chemical formulas?

  In fixed simple, whole number ratios
• What happens during a chemical reaction according to Dalton's theory?

  Atoms are rearranged
• What are the three subatomic particles?

  Protons, neutrons, and electrons
• What are isotopes?

  Atoms of the same element with different masses
• How do isotopes differ from each other?

  They have different numbers of neutrons
• What does the law of conservation of mass state?

  No mass is created or destroyed in reactions
• Who originated the law of conservation of mass?

  Antoine Lavoisier
• What does the law of multiple proportions state?

  Mass ratios of elements in compounds are whole numbers
• Who originated the law of multiple proportions?

  John Dalton
• What does the law of constant composition state?

  Pure compounds have the same mass proportions of elements
• Who originated the law of constant composition?

  Joseph Proust
• How is the mass ratio calculated in a compound?

  Place larger mass element on top
• What did J.J. Thomson discover in 1897?

  The negative charge of electrons
• What was the purpose of Millikan's oil drop experiment?

  To determine the charge of an electron
• What equipment did Millikan use in his experiment?

  Oil droplets, charged plates, and X-rays
• What is radioactivity?

  Spontaneous emission of high-energy radiation
• Who discovered the three types of radiation?

  Ernest Rutherford
• What are the three types of radiation?

  Alpha, beta, and gamma rays
• What model did J.J. Thomson propose for the atom?

  The plum pudding model
• What did Rutherford's gold foil experiment demonstrate?

  The existence of a positively charged nucleus
• Who assisted Rutherford in his gold foil experiment?

  Hans Geiger and Ernest Marsden
• What happens to some alpha particles in the gold foil experiment?

  They are deflected by the nucleus
• What did Rutherford conclude about the atom's structure?

  Most of the mass is in the nucleus
• What is the nuclear model of the atom?

  It has a dense nucleus with electrons surrounding
• What forces exist within the nucleus?

  Nuclear force and electrostatic force
• What must be true for a stable nucleus?

  Nuclear force must exceed electrostatic force
• What is the atomic mass unit (amu)?

  One twelfth the mass of a carbon-12 atom
• How is the relative mass of subatomic particles expressed?

  In atomic mass units (amu)
• What is the atomic number (Z)?

  Number of protons in an atom
• How do you calculate the number of neutrons?

  Mass number (A) - Atomic number (Z)
• What is isotope notation?

  A/Z X representation of isotopes
• How is atomic mass calculated?

  Using isotopic masses and percent abundances
• What does the periodic table represent?

  A systematic organization of elements
• How are elements arranged in the periodic table?

  By increasing atomic number (Z)
• What are the three classifications of elements in the periodic table?

  Metals, metalloids, and nonmetals
• What are the properties of metals?

  Luster, conductors, opaque, malleable