Chemistry midterm

  1. Accuracy
    how close a measurement gets to a value
  2. precision
    the measure of how close a series of measurements are to one another
  3. formula for calculating percent error
    |(accepted value - experimental value) / accepted value | * 100
  4. Law of conservation of matter and energy
    matter and energy can be neither created nor destroyed
  5. Absolute zero in celsius and Kelvin
    0 K -273C
  6. Matter is
    anything that occupies space
  7. Physical property, examples
    a quality you can observe, heavy, purple, soft
  8. Chemical property, examples
    ability to undergo a chemical change, rust, burn, explode
  9. Define element
    the simplest form of matter that has a unique set of properties
  10. define compound
    a substance that contains two or more elements chemically combined in a fixed proportion
  11. what two things are classified as pure substances
    elements and compounds
  12. what is a mixture
    a physical blend of two or more substances that are not chemically combined
  13. Homogeneous mixture
    uniform mixture
  14. Heterogeneous mixture
    not uniform
  15. Democritus
    believed atoms were indivisible and indestructible, small round attom
  16. Dalton
    atomic theary, tiny indestructible particles with no internal structure
  17. J. J. Thomson
    plubpudding theory, discovered electrons
  18. Rutherford
    cathode ray tube, discovered nuclues, the protons and nutrons are located in the nucleus and the electrons are distributed around the nucleus and occupy almost all the volume of the atom
  19. Atoms are composed of
    protons nuetrons, and electrons
  20. what does "amu" stand for
    atomic mass unit
  21. the mass of an element is the total number of
    protrons and neutrons
  22. define atom
    the smallest particle of an element that retains it's identity in a chemical reaction
  23. C-12 and C-14 are isotopes. What does that mean
    both contain carbon but have different numbers of nuetrons
  24. when an electron jumps from the excited state to the ground state, is __________ energy
  25. Difference between ground state and excited state
    • ground state- lowest energy level
    • excited state- jumps to a higher energy level
  26. Aufbau principle
    electrons must occupy the first orbitals of the lowest energy level first
  27. Pauli Exclusion
    an atomic orbital may hold at most two electrons
  28. Hunds rule
    electrons occupy orbitals of the same energy ina way that makes the number of electrons with the same spin direction as large as possible.
  29. what was mendeleev's contribution to the periodic table
    arranged the elements in order of increasing atomic mass
  30. how did mosely change mendeleev's periodic table
    determined an atomic number for each known element
  31. Periodic law
    when elements are arranged in order of increasing atomic number there is a periodic repitition of their physical and chemical properties
  32. row on the periodic table is called
  33. columns on a periodic table are called
  34. Group 1
    alkali metals
  35. Group 2
    alkaline earth metals
  36. group 7
  37. group 8
    noble gases
  38. the D block
    transition metals
  39. the f block
    inner transition metals
  40. elements on the staircase
  41. a metal _________ electrons when forming ionic bonds
  42. nonmetals normally ________ electrons when forming ionic bonds
  43. Define ionization energy and state its trand on the periodic table
    the enerfy required to remove an electron from an atom in its gaseaous state

    snow man in top right corner
  44. define electronegativity and state its trend on the period table
    • the ability of an atom to attract electrons when the atom is in a compound
    • snowman top right corner
  45. Define atomic radius and state its trend on the periodic table
    • one half the distance between the nuclei of two atoms of the same element when the atoms are joined
    • snowman bottom left corner
  46. When K turns into K+ does it get larger or smaller
    smaller, with one less electron to pull on the nucleus can pull harder on the other electrons causing it to shrink
  47. When O turns into O-2 does it get larger or smaller
    larger added electron increses the size of the electron
  48. What is the difference between ionic bond and covalent bond
    • Ionic bonds combine metals and nonmetals
    • covalent bonds combine only nonmetals
  49. CH4
  50. NH3
  51. Prefix -Tetra
  52. Prefix- penta
  53. Prefix- hexa
  54. Prefix- hepta
  55. Prefix- octa
  56. prefix- 9
  57. prefix- deca
  58. Adding or subtracting sigfigs
    lowest number decimal point
  59. Multiplying dividing sigfigs
    lowest number of sigfigs
  60. SI unit for mass
  61. Number of sigfigs in 100045
  62. Number of sigfigs in 0.000000000389
  63. Number of sigfigs in 1000.
  64. Number of sigfigs in 9.89000
  65. list the metric prefixes in order from largest (kilo) to smallest (micro)
    kilo, deci, centi, milli, micro
  66. Conversion for celcius into kelvin
    K= C + 273
  67. distilation
    a process used to separate dissolveed solids from a liquid which is boiled to produce a vapor that is then condensed into a liquid
  68. isotopes
    atoms of the same element that have the same atomic number but different atomic masses due to a different number of neutrons
  69. ion
    atom or group of atoms that has a positive or negative charge
  70. representative elements
    group 1A through 7A
Card Set
Chemistry midterm
Chemistry 1