Chemistry: FINAL EXAM
What is the equilibrium constant expression for the following equilibrium reaction? 2N 2 O(g) + O 2 (g) 4NO(g)
(3rd option) Keq = [NO]^4 [NO]^4 / [N2 O]^2[0z]
Which of the following characteristics is the kinetic molecular theory based on?
* All matter is in continual random motion. * All matter is made up of atoms and molecules that have mass.
Strontium, a group 2 element with an electron configuration of 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 , will form a _____ ion in a chemical bond.
+2
Determine the oxidation number of the element that is underlined within the compound. Ba Cr O 4
+6
Given the chemical equation, predict the ΔS system for the change. C 12 H 22 O 11 (s) C 12 H 22 O 11 (aq)
+ΔS
Use the standard enthalpies of formation for the reactants and products to solve for the ΔH rxn for the following reaction. (The ΔH f of C 2 H 4 is 52.26 kJ/mol, CO 2 is -393.509 kJ/mol, and H 2 O is -241.818 kJ.) C 2 H 4 (g) + 3O 2 (g) 2CO 2 (g) + 2H 2 O(g) ΔH rxn = _____ The reaction is _____
-1,322.91 kJ exothermic
Convert 32 K to degrees Celsius. 32 K = _____ °C
-241
How many moles are present in 16.9 g of Al 2 O 3 ?
0.166 mol
Two hundred forty-eight milliliters of an acid with an unknown concentration are titrated with a base that has a concentration of 1.4 M. The indicator changed color when 82 milliliters of base were added. What is the concentration of the unknown acid?
0.46 M
Given the following balanced reaction of hydrogen peroxide decomposing to form oxygen gas and water, how many moles of oxygen gas, O 2 , are produced from 0.980 moles of hydrogen peroxide?
0.490 mol
A student collects 285 mL of O 2 gas at a temperature of 15°C and a pressure of 0.983 atm. The next day, the same sample occupies 292 mL at a temperature of 11°C. What is the new pressure of the gas?
0.946 atm
Calculate the number of molecules present in 2.25 mol H 2 SO 4 .
1.35 x 10 24 molecules
What is the molarity of a solution that contains 612 grams of CaCl 2 in 3.04 liters of solution?
1.81 M
Students asked to measure the temperature of a reaction beaker recorded the following temperatures. 103.7°C, 108.4°C, 105.8°C, 104.6°C The actual temperature is 105.1°C. Which measurement is the most precise?
104.6°C
If a sample of copper with a density of 8.90 g/cm 3 displaces 13.0 mL of water when placed in a beaker, what is its mass?
116 g
What would be the formula for an alkane that contains 26 hydrogen atoms? C_____H 26
12
Calculate the ΔG for the following system. Then state if the system is spontaneous or not spontaneous. ΔH = 147 kJΔS = -67.0 J/KT = 149 °C
175 kJ; not spontaneous
If a chemist wants to make 575 milliliters of 0.75 M HCl solution from a stock solution of 2.0 M HCl, how many milliliters of the stock solution would the chemist need to use?
220 mL
What is the molecular weight (mass) for Ba(NO 3 ) 2 ?
261.34 g/mol
Determine the mass of the object below to the correct degree of precision. Use this media to help you complete the question.
265.8 g
Given the following balanced reaction between hydrochloric acid and oxygen gas to produce water and chlorine gas, how many grams of chlorine gas, Cl 2 , are produced from 27.8 g of hydrochloric acid and excess oxygen? (To find the molar mass in the problem, use the periodic table and round the mass to the hundreds place for calculation.)
27.0 g
How many significant figures are in 136,000 mL?
3
Answer the questions about the following reaction. 2Al(s)+ 3Pb(N0 3 ) 2 (aq) 2Al(N0 3 ) 3 (aq) + 3Pb (s): How many molecules of Pb(N0 3 ) 2 are used in the reaction? How many oxygen atoms are used in the reaction? How many moles of Al(N0 3 ) 3 are formed? What is the mole ratio of Pb(N0 3 ) 2 to Al(N0 3 ) 3 ?
3 6 2 3/2
Which of the following is not equal to 325 cg?
3.25 x 10 ^5 µg
How many molecules are found in 0.589 moles of N 2 ?
3.55 x 10 ^23 molecules
A cube has dimensions of 5.5 cm, 3.0 cm, and 2.0 cm. What is its volume?
33 cm ^3
A chemist needs 1.36 mol of strontium bromide, SrBr 2 , for a reaction. What mass of strontium chloride should the chemist use?
337 g
Express the following number in scientific notation. 46,000,000 = _____
4.6 x 10 ^7
What is the volume of the fluid in the graduated cylinder measured to the correct degree of precision? Use this media to help you complete the question.
43.4 mL
Pikes Peak is 4,301 meters high. How many centimeters high is the mountain?
430,100 cm
The elements in group 15 all have _____ valence electrons.
5
How many grams of NaOH are needed to make 0.250 liter of a 0.500 M solution of NaOH?
5.00 g
How many valence electrons are represented in the following electron configuration? 1s 2 2s 2 2p 6 3s 2 3p 4
6
Calculate the answer. Express it in scientific notation and include the correct number of significant figures. (12 x 10 4 ) x (5 x 10 -2 ) = _____
6 x 10 ^3
Find the density of an object that has a mass of 66 g and a volume of 10 cm 3 .
6.6 g/cm ^3
What is the molar mass of carbonic acid, H 2 CO 3 ? (Round to four significant figures only.)
62.01 g
How is the number 7.89 x 10 3 expressed in regular numerals?
7,890
What would be the pOH of an HNO 3 solution if the [H+] = 3.26 x 10 -6 moles/liter?
8.51
Which of the following shows the proper configuration of a straight chain isomer of nonane?
A
What is the chemical formula for a compound between Al and F?
AIF 3
Which of the following is a chemical change?
An ice pack is shaken and squeezed and becomes cold.
The formula P 1 V 1 = P 2 V 2 applies to _____.
Boyle's law
Predict which atom has the higher ionization energy.
CI
Which of the following is the correct chemical formula for Cs and Br?
CsBr
Particles formed from ionic bonding are called ions.
False
According to periodic trend, which of the following most likely has the highest ionization energy?
Ne
J.J. Thompson experimented with cathode rays and how they traveled through various gases. Through his experiments, he discovered electrons. His atomic model was known as the _____.
Plum pudding model
Choose the element described by the following electron configuration. 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1
Potassium
According to the periodic trend, which of the following is most likely to have the lowest electronegativity?
Rb
Given the table below, what is the chemical formula for a compound between Rb and the nitrate ion NO 3-1 ? nitrate ion NO 3-1phosphate PO 4-3sulfate SO 4-2acetate C 2 H 3 O 2-1ammonium NH 4+1chromate CrO 4-2carbonate CO 3-2dichromate Cr 2 O 7-2permanganate MnO 4-1sulfite SO 3-2
RbNO 3
Hans Geiger, along with ________ , used a scintillation counter (later known as the Geiger counter) to measure radioactivity.
Rutherford
Which of the following results from Rutherford's gold foil experiment was evidence that the proton was part of an atom's nucleus?
Some of the alpha particles bounced straight back off the foil and stuck to the front side of the film.
An _____ is a hydrocarbon in which one or more hydrogen atoms is replaced by a -COH group.
aldehyde
Which group of elements contains the most reactive metals?
alkali metals
Which of the following is not a property of gases?
all gases are diatomic
Balance the reaction which forms ions. Choose "blank" if no coefficient other than 1 is needed. Ba(NO 3 ) 2 ____ Ba +2 + ______ NO 3 -
blank 2
Balance the following equation. Choose "blank" if no coefficient other than 1 is needed. _____ Pb + ______ AgNO 3 _____ Pb(NO 3 ) 2 + ______ Ag
blank 2 blank 2
Pure ammonia (NH 3 ) is an example of a(n) _____.
compound
Choose the best base unit and prefix for measuring the following. The diameter of a large pizza:
decimeter
A chemist places a flask containing the reactants in an ice bath. This will _____ the rate of the reaction.
decrease
What type of reaction is represented by the following example? 2CO 2 (g) + 4H 2 O (l) + 1452 kJ 2CH 3 OH (l) (g) + 3O 2 (g)
endothermic
Tastes and odors that are naturally found in fruits or are used in candies, flavorings, and perfumes are often the result of _____.
esters
In the formation of table salt, the product, NaCl, has less energy than the reactants, Na and Cl 2 . This reaction is ____
exothermic
What type of nuclear reaction produces a nucleus with a larger mass from nuclei of lower masses?
fusion
Elements in group 15 will _______ electrons to obtain a noble gas structure. How many electrons will the element gain or lose in order to obtain a noble gas structure? _______
gain 3
A straight chain hydrocarbon with the formula C 5 H 8 _____.
has a triple C-C bond
Gases and plasma _____.
have no shape and no definite volume
Choose the answer that best describes what kind of substance air is.
homogeneous mixture
Choose the answer that best describes what kind of substance ocean water is.
homogeneous mixture
According to electronegativity difference, what type of bond are potassium and chlorine most likely to form?
ionic
Potassium and chlorine are most likely to form what type of bond?
ionic
In an endothermic reaction, energy _____.
is absorbed by the reaction
What element is missing in the following nuclear equation?
lead
C 6 H 14 has a _______ boiling point than C 11 H 24 .
lower
The following are units for mass except _____.
mL
What type of solid conducts electricity?
metallic
A student takes three beakers and places 250 milliliters of water in each. The student then adds a cube of sugar to all three beakers. The first beaker is stirred, the second beaker is heated, and the third beaker is left alone. Which dissolves faster?
not enough information
Choose whether the process below is spontaneous or not spontaneous. A house is built.
not spontaneous
An observation in science should be
objective
The following statement is a(n) _____. There is a significant difference between how elderly people and young people feel about politics.
opinion
Which elements in the following groups are most likely to not show similar properties?
oxygen, bromine, calcium
Freezing, boiling, and evaporation are all examples of _____.
physical change
Identify the following example as a physical or chemical change. Moisture in the air forms beads of water on a cold window pane.
physical change
Identify the following as an example of a physical property or a chemical property. Barium melts at 725°C.
physical property
Identify whether the following example is qualitative or quantitative data. the length of a rod:
quantitative
In the following reaction, is the nitrogen reduced or oxidized? 2Cu 2 O + 2NO 4CuO + N 2
reduced
Hexane, C 6 H 14 , is a(n) ______ hydrocarbon.
saturated
The molecular weight of nitrous oxide, NO, is 30.006 a.m.u., and the molecular weight of carbon monoxide, CO, is 28.01 a.m.u., so NO diffuses _____ CO.
slower than
According to the hardness scale, quartz is ____ than diamond.
softer
A(n) ________ is a homogenous mixture in which the solute is completely dissolved in the solvent.
solution
The scientific method is a step-by-step process that attempts to _____ a problem.
solve
Lye works to dissolve oil and grease because it is a _____.
strong base
Which of the following is a correct representation of the isotope of sulfur that has 19 neutrons?
sulfur-35
Other than carbon being relatively small, what is another reason that carbon can form so many compounds?
the ability to form ring structures and chains
An ideal gas is a ____ gas
theoretical
Radioactivity is the process of nuclear decay.
true
A solution has a Ca 2+ concentration of 0.049 M and an F- concentration is 0.147 M at equilibrium. The value of k sp for CaF 2 at 25°C is 4.0 x 10 -11 . Will this solution form a precipitate?
yes
Is the following chemical equation balanced? 4Al + 3O 2 2Al 2 O 3
yes
