1.Definite proportions and conservation of mass are discussed in chemistry. Both are characterized as:

a.theories
b.facts
c.hypotheses
xd.laws
e.experiments

2.A theory can be discarded if a(n) _________ proves it to be contrary to fact.

a.law
xb.experiment
c.congressional resolution
d.dogma

3.The state of matter of a given substance with the least kinetic energy is:

a.gas
b.liquid
xc.solid
d.all are the same

4.Substances can be

a. heterogeneous
xb. elements or compounds
c. mixtures and solutions
d. nonuniform

5. A skier moving at the top of the slope has

a. kinetic energy
b. potential energy
xc. both kinetic and potential energy
d. none above

6. Melting is a ______________process.

a. chemical
xb. physical
c. nuclear
d. atomic

7. Heat can be measured in

xa. calories
b. oC
c. oF
d. a & c
e. a & b

8.Find the density if a 4.0 Kg object has a volume of 0.5 liter(L).

xa. 8 Kg/L
b. 0.5 Kg/L
c. 4
d. 0.5

9.Compute the number of inches in 10 cm. 2.54 cm = 1 in

choose the best set-up

b.10 cm x 1 in = x
2.54 cm

xc.2.54 cm x 1 in. = x
10 cm

d. 10 in x 2.54 cm x 1 in = x

10.The following is a list of substances postulated by a student as possible products in expt 1.

Possible products

The reactants (starting substances) were H2O (water), Cu(SO4)(copper sulfate), Al (aluminum), and NaCl (salt). The substance(s) least likely to be produced given the reactants is(are):

11.Given the reaction:

2Al + 3CuCl2 = 2AlCl3 + 3Cu
27g + 201g ? 96 g

The amount of AlCl3 should be:

xa. 132 g
b. 264 g
c. 54 g
d. 27 g

12. Scientific information is

a. lawful
b. tentative
c. testable
d. explanatory
xe. b,c,d

13.In expt 3, melting & freezing,

a.melting is a physical change because all one does is liquefy a solid
b. are chemical processes
c. have different temperatures for water
d.both parts of this experiment used calories in the calculation

14.In the fire extinguisher experiment/demo, it was seen

xa. that some molecules have more energy than others
b.all molecules of carbon dioxide have the same energy at room temperature
c.the cylinder got warm from molecular friction
d.carbon dioxide is less dense than air so one aims the hose below the fire.

15.Find the isotopes

element atomic # atomic mass
A 45 103
B 46 103
C 44 102
D 44 101
E 44 103

a. A & B & E
xb.C & D & E
c. B & C
d. A & D
e. B & D

16.Element 87 would react similarly to element

a.2
b. 85
c. 86
d. 3
e. 4

17.Elements 3 through 10

a. are all metals
xb. react differently
c. have the same number of valence electrons
d.react in a similar way
e. none above

18.Solutions

xa.have at least two miscible substances mixed homogeneously
b.are pure substances
c.are elements
d.are heterogeneous mixtures

19.The last, partially filled energy level for N would be

a. 2s22p5
b. 2s32p2
xc. 2s22p3
d. none above

20.Molecules of sodium thiosulfate when above the freezing point would have

xa.more kinetic energy than the solid
b.less kinetic energy than the solid
c.SAME kinetic energy as the solid
d.less potential and less kinetic energy than the solid

21.Column VIIA (7a) is called the

xa. halogens
b. metals
c. inert gases
d. metalloids
e. alkaline earths

22.Given the complete nuclear equation shown below:

14N + 1n = 14C + 1H
7 0 6 1
a. This equation shows a transmutation
b. This equation shows an isotope of C
c. This is a chemical equation
xd. a & b only

23.The life of carbon 14 is about 5000 years. It is a beta emitter. If at this instant one has 1000 Kg of this isotope there should be ? Kg of the radioactive isotope left after 10000 years.

a. 333 Kg
b. 250 Kg
c. 333 g
d. 500 Kg
xe. 250 g

24.Carbon 14 is a beta emitter. Therefore it

xa. emits electrons
b. emits protons
c. emits helium nuclei
d. emits light
e. all above

25. Na

xa. is a metal
b. has 23 electrons
c. has 23 protons
d. is an alkaline earth element

26.We know (within the limits of scientific knowledge) that the earth is about 4.5 billion years old. The main method for determining this age is:

xa. radioisotopic dating
b. tree ring dating
c. ancient writings
d. rate of thermal cooling of the prehistoric earth
e. a & d above

27. Nuclear fission is

a. putting atoms together to make a nuclear explosion
b. splitting of water to make hydrogen and oxygen
xc. splitting uranium-235 to make isotopes of Sr & Xe.
d. both b & c.

28.When an electron is in an excited state, it will eventually

xa. return to the ground state giving off light
b. leave the atom
c. stay where it is until a seed crystal is added
d. all above

29.Elements that should react differently

a. 20, 38, 56
b. 8, 34, 52
xc. 7, 8, 9
d. 37, 55, 87

30. Element 68 is

xa. inner-transition
b. transition
c. alkali
d. halogen
e. none above