According to modern atomic theory, it is nearly impossible to determine an electrons exact

1
80.7

• According to modern atomic theory, it is nearly
  impossible to determine an electrons exact
• a. color. c. charge
• b. position. d. mass.

2
78.9

• A material that can be represented by a chemical
  formula is
• a. an element. c. a homogeneous solution.
• b. a mixture. d. a pure substance.
• A formula of symbols used to represent a
  compound
• a way to write a compound's name using symbols
• notation made with numbers and chemical symbols
  indicating the composition of a compound and the
  number of atoms of an element in one molecule.

3
71.9 98

FIG. 9.1 Referring to Fig 9. 1, what happens
to the temperature of a substance as it changes
phase from a solid to a liquid when heat energy
is increased over time? a. increases c.
stays the same b. Decreases d. heat energy
not involved in phase change
4

• When a fixed sample of gas increases in volume,
  it must also
• a. decrease in pressure. c. Either (a) or (b)
• b. increase in temperature. d. Both (a) and (b)

P1V1 P2V2 T1 T2
5

• The smallest unit of a substance that behaves
  like the substance is
• a. an element. c. a molecule.
• b. an atom. d. a compound.

Matter of definite composition and properties.
For example, every pure element is a
different substance. Every pure compound
is a different substance. Salt water is not a
substance. It is a mixture of two substances -
sodium chloride and water. Its composition and
therefore its properties are not fixed. Gasoline
is not a substance. It is a mixture of
hydrocarbons and depending on the composition of
the gasoline mixture, gasoline's properties can
vary.
In chemistry, a molecule is defined as a
sufficiently stable, electrically neutral group
of at least two atoms in a definite arrangement
held together by very strong chemical bonds.
This definition has evolved as knowledge of the
structure of molecules has increased. Earlier
definitions were less precise defining molecules
as the smallest particles of pure chemical
substances that still retain their composition
and chemical properties.3 This definition
often breaks down since many substances in
ordinary experience, such as rocks, salts, and
metals, are composed of large networks of
chemically bonded atoms or ions, but are not
made of discrete molecules.
6
61.4 120

• When a solution of an acid reacts with a solution
  of a base, hydronium ions react with hydroxide
  ions to form
• a. a salt. c. a weaker base.
• b. a stronger acid. d. water.

7
56.0 4

• Which SI prefix means one million?
• a. kilo- c. giga-
• b. mega- d. milli-

8
50.9

• Covalent bonds are formed between
• a. ions such as Na, Cl-. c. nonmetal atoms such
  as CO, CH
• b. metal atoms such as Cu. d. compounds such as
  H2O NaCl.

9
49.1

• The decimal equivalent of 10-2 is
• a. 100. c. 0.1.
• b. 10. d. 0.01.

10
49.1

• You put 1 gram of salt into 1 liter of water and
  stir. The resulting liquid is an example of
• a. a pure substance. .
• b. a heterogeneous mixture.
• c. a homogeneous mixture
• d. an immiscible mixture.

11
49.1

• Grandma Johnson, related to NASCAR driver Jimmy,
  is driving around North Guilford on Lake Shore
  Drive at 53,645 cm/minute. Is her speed
  reasonable for that local road?
• a. Yes c. Not a possible speed
• b. No d. Way to slow for Grandmother of
  Race Car driver

12
49.1

• Which is an example of a neutralization reaction?
• a. NaOH ? Na OH-
• b. HNO3 H2O ? H3O NO3-
• c. 2H2 O2 ? 2H2O
• d. H3O OH- ? 2H2O

13
45.6

• Which of the following is not a potential sign of
  chemical change?
• a. release of gas
• b. evaporation of water
• c. change of color
• d. production of gas

14
45.6

• A compound differs from a mixture because it
• a. always remains frozen even at high
  temperatures.
• b. is formed from two cations.
• c. always contains the same elements in the same
  proportion.
• d. can form only in the presence of heat energy.

15
45.6

• When methane reacts with abundant amounts of
  oxygen, the products are
• a. carbon dioxide and water.
• b. carbon monoxide and water.
• c. soot and water.
• d. simple sugar and oxygen.

16
43.9
type of material average of 5 trials temperature
change after 5 minutes in deg. C no cover
15 wax paper 9 aluminum foil 6 plastic
wrap 3 black paper 5 white paper 5

• The material achieving the least heat loss was
  impervious to water and
• a. a good conductor c. ductile
• b. a synthetic polymer d. expensive

17
38

• CPT The atomic number of iron is 26, and the
  atomic mass is 55.847 What do these numbers
  mean in regard to protons, electrons and
  neutrons?
• a. There are 26 each of protons and neutrons, and
  the rest of the mass is the result of the
  electrons.
• b. There are 26 protons and 26 electrons. Some
  atoms of iron have 29 neutrons the .847 show
  that there is more than one isotope of iron.
• c. There are 26 protons and 29 neutrons. Each
  particle has an atomic mass of 1
• d. There are 26 protons and 26 neutrons. Since
  neutrons have slightly more mass than protons,
  the mass is greater than 52.

18
31.6

• CPT The chemical properties of an element are
  determined by its
• a. atomic mass
• b. proton number
• c. electron arrangement
• d. atomic size

19
15.8

• CPT Which of the following is best classified as
  a compound?
• a. Helium (He) because it contains only one type
  of atom
• b. Oxygen (O2) because it contains two of the
  same type of atoms
• c. Carbon dixide (CO2), because it contains two
  different types of atoms
• d. Manganese (Mn), because it contains a metal
  and a nonmetal

20
10.5

• CPT Which element in this group would be the
  least likely to react with other elements?
• a. Boron c. Neon
• b. Carbon d. Oxygen