Download CHEM 1211K Test I MULTIPLE CHOICE. (3 points each) 1

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts

Tennessine wikipedia , lookup

Isotopic labeling wikipedia , lookup

Chemical element wikipedia , lookup

Extended periodic table wikipedia , lookup

Ununennium wikipedia , lookup

Unbinilium wikipedia , lookup

Isotope wikipedia , lookup

History of molecular theory wikipedia , lookup

Transcript
CHEM 1211K
Test I
MULTIPLE CHOICE. (3 points each)
1) Consider a mixture consisting of sand in salt water. This mixture could be separated into its
three components (sand, salt, and water) by first __________ the mixture and then
__________ the remaining mixture.
A) filtering, filtering
B) filtering, distilling
C) distilling, distilling
D) evaporating, grinding
E) distilling, filtering
2)
Which one of the following is a pure substance?
A) salt water
B) concrete
C) milk
D) wood
E) elemental copper
3)
Which states of matter are significantly compressible?
A) liquids and gases
B) gases only
C) solids and liquids
D) liquids only
E) solids only
4)
If matter is uniform throughout and cannot be separated into other substances by physical
means, it is __________.
A) a heterogeneous mixture
B) either an element or a compound
C) an element
D) a compound
E) a homogeneous mixture
5)
Which one of the following is an intensive property?
A) heat content
B) amount
C) temperature
D) mass
E) volume
6)
Which of the following are chemical processes?
A) rusting of a nail
B) freezing of water
C) decomposition of water into hydrogen and oxygen gases
D) compression of oxygen gas
E) A and C
7)
The temperature of 25oC is __________ in Kelvins.
A) 103
B) 138
C) 248
D) 298
E) 166
1.035 x 10-4 L = __________ mL
A) 0.1035
B) 0.01035
C) 1.035 x 10-7 D) 1.035
E) 1.035 x 107
8)
9)
The density of silver is 10.5 g/cm3. What would be the mass (in grams) of a piece of silver
that occupies a volume of 23.6 cm3?
A) 0.445g
B) 248g
C) 2.25g
D) 112g
E) 23.6g
10) Accuracy refers to __________.
A) how close a measured number is to the calculated value
B) how close a measured number is to zero
C) how close a measured number is to infinity
D) how close a measured number is to the true value
E) how close a measured number is to other measured numbers
11) A wooden object has a mass of 10.782 g and occupies a volume of 13.72 mL. What is the
density of the object determined to an appropriate number of significant figures?
A) 8 x 10 -1 g/mL
B) 7.9 x 10-1 g/mL
-1
C) 7.86 x 10 g/mL
D) 7.859 x 10-1 g/mL
-1
E) 7.8586 x 10 g/mL
12) The number with the most significant zeros is __________.
A) 0.00002510
B) 250000001
C) 0.02500001
D) 2.5100000
E) 2.501 x 10-7
13) The recommended adult dose of Elixophyllin, a drug used to treat asthma, is 6.0 mg/kg of
body mass. Calculate the dose in milligrams for a 115-lb person. 1 lb = 453.59 g.
A) 1.5
B) 24
C) 313
D) 1,521
E) 3.1 x 10 5
14) What decimal power does the abbreviation Milli represent?
A) 1 x 10-3
B) 1 x 10 9
C) 1 x 10-6
D) 1 x 10 3
E) 1 x 10 6
15) Methane and ethane are both made up of carbon and hydrogen. In methane, there are 12.0 g of
carbon for every 4.00 g of hydrogen, a ratio of 3:1 by mass. In ethane, there are 24.0 g of
carbon for every 6.00 g of hydrogen, a ratio of 4:1 by mass. This is a statement of the law of
__________.
A) octaves
B) constant composition
C) conservation of matter
D) conservation of mass
E) multiple proportions
16) In the symbol below, X = ___________
13
6
A) N
B) C
C) Al
X
D) K
E) not enough information
17) The charge on an electron was determined in the __________.
A) atomic theory of matter
B) Rutherford gold foil experiment
C) Millikan oil drop experiment
D) Dalton atomic theory
E) cathode ray tube, by J. J. Thompson
18) __________ and __________ reside in the atomic nucleus.
A) Protons, electrons
B) Protons, neutrons
C) Electrons, neutrons
D) none of the above
E) Neutrons, only neutrons
19) In the Rutherford nuclear-atom model, __________.
A) the light subatomic particles, protons and neutrons, reside in the nucleus
B) the three principal subatomic particles (protons, neutrons, and electrons) all have essentially
the same mass
C) the heavy subatomic particles, protons and neutrons, reside in the nucleus
D) the three principal subatomic particles (protons, neutrons, and electrons) all have essentially
the same mass and mass is spread essentially uniformly throughout the atom
E) mass is spread essentially uniformly throughout the atom
20) Cathode rays are deflected away from a negatively charged plate because __________.
A) they are negatively charged particles
B) they are not particles
C) they are positively charged particles
D) they are neutral particles
E) they are emitted by all matter
21) Of the following, the smallest and lightest subatomic particle is the __________.
A) nucleus
B) proton
C) neutron
D) electron E) alpha particle
22) The atomic number indicates __________.
A) the number of different isotopes of an element
B) the number of neutrons in a nucleus
C) the number of atoms in 1 g of an element
D) the total number of neutrons and protons in a nucleus
E) the number of protons or electrons in a neutral atom
23) Which combination of protons, neutrons, and electrons is correct for the isotope of copper,
63
29 Cu ?
A) 34 p+, 34 no, 29 eB) 29 p+, 34 no, 29 e+
o
C) 63 p , 29 n , 63 e
D) 29 p+, 29 no, 63 eE) 34 p+, 29 no, 34 e24) Which one of the following is not one of the postulates of Dalton's atomic theory?
A) During a chemical reaction, atoms are changed into atoms of different elements.
B) Each element is composed of tiny, indivisible particles called atoms.
C) Compounds are formed when atoms of different elements combine.
D) Atoms of an element are not changed into different types of atoms by chemical reactions.
E) All atoms of a given element are identical to each other and different from those of other
elements.
25) Different isotopes of a particular element contain the same number of __________.
A) subatomic particles
B) protons, neutrons, and electrons
C) neutrons
D) protons and neutrons
E) protons
Problems (SHOW ALL WORK ON THIS PAPER)
(5 points) The density of benzene at 15oC is 0.8787g/mL. Calculate the mass of 0.1500L of
benzene.
D=
0.8787 g / mL =
mass
volume
mass
(0.1500 L )(1000mL
)
1L
mass=0.8787 g / mL 0.1500L 1000mL
(
(
1L
))
(10 points) A children’s pain relief elixir contains 80mg acetaminophen per 0.50 teaspoon. The
dosage recommendation for a child who weight between 24 and 35 lb is 1.5
teaspoons. What is the range of acetaminophen dosages, expressed in milligram
acetaminophen/ kg body weight, for children, who weigh between 24 and 35 lb?
 80mg 
1.5tsp
 =
tsp
0
.
50


= 240 mg
25lbs
 453.59 g  1kg 
24lbs
 =

 1lb  1000 g 
= 10.886kg
240 mg drug
dose =
10.886kg
= 22.1mg / kg
35lbs
 453.59 g  1kg 
35lbs
 =

 1lb  1000 g 
= 15.876kg
240 mg drug
15.876kg
= 15.1mg / kg
dose =
(10 points) Only two isotopes of copper occur naturally. 63Cu (mass = 62.9296amu: abundance
69.17%) and 65Cu (mass = 64.9278, abundance 30.83%). Calculate the atomic weight
(average atomic mass) of copper.
This is a homework problem.
- weighted average
wt . average = (64.9278amu • (30.83 / 100)) + (62.9296amu • (69.17 / 100))
= 63.55amu