Science Mid Term

  1. What are the two main branches of science?
    natural and social
  2. What are the main branches of natural science?
    life, physical, and earth science
  3. What is technology?
    applied science
  4. What is a scientific theory?
    An explanation the has been tested by many observations
  5. What is a scientific model?
    A representation of a real event or object
  6. When can scientific theories be changed or replaced?
    when new discoveries are made
  7. Scientists use computer models to study complicated events and to
    make predictions
  8. What is a series of logical steps that is followed in order to solve a problem?
    scientific method
  9. What is the first step in the scientific method?
    making a observation
  10. How do scientists test a hypothesis?
    doing experiments
  11. What does it mean to say the "no experiment is a failure"?
    All experiments are observations of real events
  12. What is the SI unit for measuring temperature?
  13. What SI prefix means one million?
  14. What SI prefix means one one-hundredth (1/100)?
  15. Maria is 123 centimeters tall. What is her height in meters?
    1.23 meters
  16. What is matter?
    Anything that has mass and takes up space
  17. What is a substance that cannot be broken down into simpler substances?
    an element
  18. What is the smallest unit of a substance that behaves like the substance?
    a molecule
  19. A molecule of water (H2O) is made from _____ combining two hydrogen atoms and one oxygen atom.
  20. You put 1 gram of salt into 1 liter of water and stir. What is the resulting liquid an example of?
    a homogeneous mixture
  21. The chemical symbol for sulfuric acid is H2SO4. How many atoms are contained in each molecule of sulfuric acid?
  22. How many oxygen atoms are in one molecule of table sugar (C12H22O11)?
  23. The chemical formula for water, H2O, means that each water molecule contains
    2 hydrogen atoms and 1 oxygen atom
  24. What state of matter will hold its shape without a container?
  25. A liquid changes rapidly into a gas at the liquid's
    boiling point.
  26. Which of the following is not an example of a physical property?
    a) freezing point c) reactivity
    b) boiling point d) density
    c) reactivity
  27. Which of the following is an example of a physical change?

    B) dissolving salt in water
  28. Which of the following is an example of chemical change?

    B) grilling a burger
  29. Which of the following is an example of chemical change?

    A) paint fading
  30. When water is broken down, what happens to the oxygen and hydrogen atoms it is made of?
    They are rearranged to form hydrogen and oxygen gas
  31. Temperature is a measure of the average _____ energy of the particles in the object.
  32. What is the process of a liquid becoming a gas?
  33. What is the only state of matter that is not a fluid?
  34. What state of matter has a definite volume, but not shape?
  35. The heavier a particle, the ____ it moves.
  36. What determines the speed of the atoms and molecules of a particular substance?
    size of the atoms and molecules and temperature of the substance
  37. Archimedes' principle states that the buoyant force on an ______ is equal to the weight of the displaced volume of fluid.
    object in the fluid
  38. Pascal's principle states that a fluid in equilibrium enclosed by a vessel exerts pressure ______.
    equally in all directions
  39. What is the resistance of a fluid to flow?
  40. The kinetic theory states that the higher the temperature, the faster the
    particles that make up a substance move.
  41. What is the change of a substance from a solid directly to a gas?
  42. What is the law of conservation of mass?
    mass cannot be created or destroyed
  43. Why does ice float in water?
    it is less dense than water
  44. Boyle's law relates the pressure of a gas to its
  45. When a fixed sample of gas increases in volume, it must also
    decrease in pressure OR increase in temperature
  46. Charles's law relates the volume of a gas to its
  47. Gay-Lussac's law relates the temperature of a gas to its
  48. Pressure is calculated by dividing force by the _____ over which the force is exerted.
  49. Bernoulli's principle describes the property of a
    fluid in motion.
  50. Buoyant force is the _____ force exerted on an object immersed or floating on a liquid.
  51. As the temperature of a fixed amount of gas at constant volume decreases, its pressure
  52. As the volume of a fixed amount of gas at constant temperature decreases, its pressure
  53. Dalton's atomic theory stated that every element was made of atoms that could not be subdivided, atoms of the same element are alike, and
    atoms can join to form molecules.
  54. Why was Dalton's atomic theory accepted?
    there was evidence to support it.
  55. Which statement is true according to Dalton's theory?

    C) Atoms of the same element are exactly alike.
  56. Which statement about the atomic nucleus is correct?

    B) The nucleus is made of protons and neutrons and has a positive charge.
  57. What is the charge of an electron?
  58. Why do atoms have no electric charge?
    they have an equal number of electrons and protons
  59. According to Bohr's model of the atom, electrons behave like
    planets orbiting the sun.
  60. According to Bohr's theory, an electron's path around the nucleus defines its
    energy level.
  61. According to modern atomic theory, it is nearly impossible to determine an electron's exact
  62. What is the order of elements in the periodic table based on?
    the number of protons in the nucleus
  63. Atoms of elements that are in the same group have the same number of
    valence electrons.
  64. Valence electrons determine an atom's
    chemical properties.
  65. Ionization refers to the process of
    losing or gaining electrons.
  66. Why is a lithium ion much less reactive than a lithium atom?
    it has a full outermost energy level
  67. Oxygen's atomic number is 8. This means that an oxygen atom has
    eight protons in its nucleus.
  68. An atom's mass number equals the number of
    protons plus the number of neutrons.
  69. Which statement about an element's average atomic mass number is correct?

    C) It is a weighted average, so common isotopes have a greater effect than uncommon ones.
  70. What is an atomic mass unit equal to?
    one-twelfth the mass of a carbon-12 atom.
  71. Which statement about the alkali metals is correct?

    D) They are located in the left-most column of the periodic table.
  72. Which statement about noble gases is correct?

    B) They exist as single atoms rather than as molecules.
  73. Semiconductors are elements that
    can conduct heat and electricity under certain conditions.
  74. Most halogens form compounds by
    gaining an electron to form a negative ion.
  75. Why are Group 18 noble gases inert?
    their outermost energy level is full.
  76. Carbon and other nonmetals are found in which are of the periodic table?
    on the right side
  77. How do transition metals such as copper or tungsten form compounds?
    by losing electrons to form positive ions
  78. A mole is an SI base unit that describes the
    amount of a substance.
  79. If the atomic mass of carbon is 12 amu, 1 mole of pure carbon will have a mass of
    12 grams
  80. Avogadro's constant is defined as the number of particles in
    one mole of a pure substance.
  81. What is molar mass?
    the mass in grams of 1 mole of a substance
  82. The average atomic mass of potassium is approximately 39 amu. What is the mass of 2.0 mol of potassium?
    78 grams
  83. You have 6.50 mol of chromium, which has a molar mass of approximately 52 g/mol. What is the mass in grams of this amount of chromium?
    338 grams
  84. You have 85.5 g of fluorine, which has a molar mass of approximately 19 g/mol. How many moles of fluorine do you have?
    4.5 mol
  85. What are the forces that hold different atoms or ions together?
    chemical bonds
  86. A mixture is different from a compound because each substance in a mixture
    retains its own properties.
  87. A compound differs from a mixture because it
    always contains the same elements in the same proportion.
  88. Each molecule of hydrochloric acid, HCl, contains one atom of hydrogen and
    one atom of chlorine.
  89. Each molecule of table sugar, C12H22O11, contains
    12 atoms of carbon.
  90. Why do gases take up a lot of space?
    their molecules have very little attraction for one another.
  91. Often atoms join so that each atom will have
    an outermost energy level that is full of electrons.
  92. An ionic bond forms between
    ions with opposite charges.
  93. Covalent bonds form between
    nonmetal atoms.
  94. In a metallic bond, the nucleus of one atom is attracted by a nearby atom's
  95. Copper is a good conductor of electricity because its electrons
    are free to move from atom to atom.
  96. In which type of bond do atoms share electrons?
    Covalent bonds
  97. The anion formed from an oxygen atom is called an
    oxide ion.
  98. The name dinitrogen tetroxide tells you that this compound contains
    two nitrogen atoms and four oxygen atoms.
  99. When copper combines with oxygen to form copper (II) oxide, the charge of the copper ion is
  100. The name for the compound with the formula Cr2O3 would be written as
    chromium (III) oxide.
  101. It is possible for different covalent compounds to have the same empirical formula because empirical formulas represent
    a ratio of atoms in the compound.
  102. A carbon atom can bond to four other atoms because it has
    four valence electrons.
  103. What is the simplest organic compound?
  104. Alkanes are hydrocarbons that contain
    single covalent bonds only.
  105. Alcohols are organic compounds that contain
    carbon, oxygen, and hydrogen.
  106. Polymers are large organic molecules that are made of
    repeating units.
  107. Which compounds have carbon-carbon double bonds?
  108. The "rings" of the DNA "ladder" are made up of
    paired monomers.
  109. Some polymers are elastic because they are made of
    cross-linked chains.
Card Set
Science Mid Term
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