CHS 1440 - Final Exam Questions &
Answers31
Becquerel called the rays he discovered uranic rays because they were emitted from minerals
that contained ____________
a. Polonium
b. Radium
c. Uranium
d. None of the above - ANSWERS-c. Uranium
Which form of radioactivity decay would be most likely to detect if it were happening in the
room next to the one you are currently in?
a. Alpha
b. Beta
c. Positron emission
d. Gamma - ANSWERS-d. Gamma
Which nuclide is most likely to undergo positron emission?
a. Si-22
b. Rb-91
c. Ar-37
d. Co-55 - ANSWERS-a. Si-22
Complete the following nuclear equation: Cm-246 + Na-12 --> n-0 4 + ?
a. No-244
,b. Md-258
c. Cf-258
d. None of the above - ANSWERS-c. Cf-258
How many significant figures are present in these measured quantities? 5.619 mm and 2.475 x
10-3 cm (respectively)
a) 6, 6
b) 3, 1
c) 3, 4
d) 4, 4 - ANSWERS-d) 4,4
Express the 59.0 °F in K
a) 138.2 K
b) 288 K
c) 180 K
d) 310.9 K - ANSWERS-b) 288 K
Provide the name, symbol, number of electrons, mass number, and atomic number of an
isotope that contains 18 protons and 19 neutrons (respectively)
a) Fluorine, F, 9, 19, 9
b) Argon, Ar, 18, 37, 18
c) Fluorine, F, 10, 18, 9
d) None of the above - ANSWERS-b) Argon, Ar, 18, 37, 18
After balancing the following equation, which would be your stoichiometric coefficients
(respectively):
C3H8(g) + O2(g) -> CO2(g) + H2O(g)
, a) 1, 2, 3, 1
b) 1, 5, 3, 4
c) 1, 2, 1, 2
d) 2, 1, 2, 1 - ANSWERS-b) 1, 5, 3, 4
In a reaction, products are ________ of the reaction arrow, reactants are _________ of the
reaction arrow, and special conditions are _________ of the reaction arrow
a) Right, left, on top
b) Left, on top, right
c) On top, left, right
d) Left, right, on top - ANSWERS-a) Right, left, on top
Complete the following statement: Data that have a small random error but otherwise fall in a
narrow range are _______________
a) Accurate
b) Precise and accurate
c) Precise
d) None of the above - ANSWERS-c) Precise
Diborane and related compounds were proposed as rocket fuels in the 1950s. A representative
reaction for this class of molecules is that of B2H6 and O2 to form B2O3 and H2O. If 516 g of
B2H6 react with 1.1 kg of O2 to form 433 g of B2O3, how much water is produce in the
reaction?
a) 1.2 x 10^3 g
b) 84 g
c) 84.1 g
d) 1183 g - ANSWERS-a) 1.2 x 10^3 g
Answers31
Becquerel called the rays he discovered uranic rays because they were emitted from minerals
that contained ____________
a. Polonium
b. Radium
c. Uranium
d. None of the above - ANSWERS-c. Uranium
Which form of radioactivity decay would be most likely to detect if it were happening in the
room next to the one you are currently in?
a. Alpha
b. Beta
c. Positron emission
d. Gamma - ANSWERS-d. Gamma
Which nuclide is most likely to undergo positron emission?
a. Si-22
b. Rb-91
c. Ar-37
d. Co-55 - ANSWERS-a. Si-22
Complete the following nuclear equation: Cm-246 + Na-12 --> n-0 4 + ?
a. No-244
,b. Md-258
c. Cf-258
d. None of the above - ANSWERS-c. Cf-258
How many significant figures are present in these measured quantities? 5.619 mm and 2.475 x
10-3 cm (respectively)
a) 6, 6
b) 3, 1
c) 3, 4
d) 4, 4 - ANSWERS-d) 4,4
Express the 59.0 °F in K
a) 138.2 K
b) 288 K
c) 180 K
d) 310.9 K - ANSWERS-b) 288 K
Provide the name, symbol, number of electrons, mass number, and atomic number of an
isotope that contains 18 protons and 19 neutrons (respectively)
a) Fluorine, F, 9, 19, 9
b) Argon, Ar, 18, 37, 18
c) Fluorine, F, 10, 18, 9
d) None of the above - ANSWERS-b) Argon, Ar, 18, 37, 18
After balancing the following equation, which would be your stoichiometric coefficients
(respectively):
C3H8(g) + O2(g) -> CO2(g) + H2O(g)
, a) 1, 2, 3, 1
b) 1, 5, 3, 4
c) 1, 2, 1, 2
d) 2, 1, 2, 1 - ANSWERS-b) 1, 5, 3, 4
In a reaction, products are ________ of the reaction arrow, reactants are _________ of the
reaction arrow, and special conditions are _________ of the reaction arrow
a) Right, left, on top
b) Left, on top, right
c) On top, left, right
d) Left, right, on top - ANSWERS-a) Right, left, on top
Complete the following statement: Data that have a small random error but otherwise fall in a
narrow range are _______________
a) Accurate
b) Precise and accurate
c) Precise
d) None of the above - ANSWERS-c) Precise
Diborane and related compounds were proposed as rocket fuels in the 1950s. A representative
reaction for this class of molecules is that of B2H6 and O2 to form B2O3 and H2O. If 516 g of
B2H6 react with 1.1 kg of O2 to form 433 g of B2O3, how much water is produce in the
reaction?
a) 1.2 x 10^3 g
b) 84 g
c) 84.1 g
d) 1183 g - ANSWERS-a) 1.2 x 10^3 g
