Chemistry Final
What is the molarity of a solution that contains 0.202 mol KCl in 7.98 L solution?
0.0253 M
2 Al(NO3)3(aq) + 3 Na2SO4(aq) --> Al2(SO4)3 (aq ) + 6 NaNO3(aq) How many L of a 0.385M sodium sulfate solution is needed to completely react with .20 L of a 0.100M aluminum nitrate solution?
0.078 L
What is the molality of a solution that contains 31.0 g HCl in 5.00 kg water? (molar mass of HCl = 36.46 g/mol)
0.170 m
The formula for carbon dioxide, CO2, can represent
1 mol of carbon dioxide molecules; one molecule of carbon dioxide; the combination of 1 atom of carbon and 2 atoms of oxygen
For the reaction represented by the equation Cl2 + 2KBr ® 2KCl + Br2, how many moles of potassium chloride are produced from 119 g of potassium bromide?
1.00 mol
For the reaction represented by the equation 2H2 + O2 ® 2H2O, how many grams of water are produced from 6.00 mol of hydrogen?
108 g
The concentration of a water solution of NaCl is 2.48 m, and it contains 806 g of water. How much NaCl is in the solution? (molar mass of NaCl = 58.44 g/mol)
117 g
For the reaction represented by the equation 2H2 + O2® 2H2O, how many moles of water can be produced from 6.0 mol of oxygen?
12 mol
How many grams of BaCl2 are needed to react with 1.40 L of a .47 M Na2SO4? Na2SO4(aq) + BaCl2(aq) --> BaSO4(s) + 2NaCl(aq)
136 g
At 7.0ºC, the volume of a gas is 49 mL. At the same pressure, its volume is 74 mL at what temperature?
150ºC
Calculate the approximate temperature of a 0.50 mol sample of gas at 750 mm Hg and a volume of 12 L.
15ºC
In the reaction represented by the equation N2 + 3H2 ® 2NH3, what is the mole ratio of nitrogen to ammonia?
1:2
For the reaction represented by the equation SO3 + H2O ® H2SO4, how many grams of sulfuric acid can be produced from 200. g of sulfur trioxide and 100. g of water?
245 g
The electron configuration of nitrogen is 1s2 2s2 2p3. How many more electrons does nitrogen need to satisfy the octet rule?
3
An NaOH solution contains 1.90 mol of NaOH, and its concentration is 0.555 M. What is its volume? (molar mass of NaOH = 40.00 g/mol)
3.42 L
For the reaction represented by the equation SO3 + H2O ® H2SO4, how many grams of sulfur trioxide are required to produce 4.00 mol of sulfuric acid in an excess of water?
320. g
In the reaction represented by the equation N2 + 3H2 ® 2NH3, what is the mole ratio of hydrogen to ammonia?
3:2
For the reaction represented by the equation 2Na + 2H2O ® 2NaOH + H2, how many grams of hydrogen are produced if 120. g of sodium and 80. g of water are available?
4.5 g
In the equation 2KClO3 ® 2KCl + 3O2, how many moles of oxygen are produced when 3.0 mol of KClO3 decompose completely?
4.5 mol
For the reaction represented by the equation 2KlO3 ® 2KCl + 3O2, how many moles of potassium chlorate are required to produce 250. g of oxygen?
5.21 mol
What mass of water must be used to make a 1.35 m solution that contains 8.20 mol of NaOH? (molar mass of NaOH = 40.00 g/mol)
6.07 kg
A sample of oxygen occupies 560. mL when the pressure is 800.00 mm Hg. At constant temperature, what volume does the gas occupy when the pressure decreases to 700.0 mm Hg?
640. mL
The volume of a gas is 93 mL when the temperature is 91ºC. If the temperature is reduced to 0ºC without changing the pressure, what is the new volume of the gas?
70. mL
In drawing a Lewis structure, each nonmetal atom except hydrogen should be surrounded by
8 electrons
For the reaction represented by the equation Cl2 + 2KBr ® 2KCl + Br2, calculate the percentage yield if 200. g of chlorine react with excess potassium bromide to produce 410. g of bromine.
91.0%
Predict what happens when calcium metal is added to a solution of magnesium chloride.
Calcium chloride forms.
Which of the following decreases the average kinetic energy of solvent molecules?
Decreasing the temperature
In the chemical equation 2Mg(s) + O2(g) ==> 2MgO(s),
Mg represents the reagent magnesium.
The Lewis structure for the ammonium ion, HF, has
Polar covalent
Predict what happens when nickel is added to a solution of potassium chloride.
Potassium chloride forms
What determines the average kinetic energy of the molecules of any gas?
Temperature
Why does the air pressure inside the tires of a car increase when the car is driven?
The air particles inside the tire increase their speed because their temperature rises.
Why would a camper near the top of Mt. Everest find that water boils at less than 100ºC?
There is less atmospheric pressure than at sea level.
When a polar molecule attracts the electron in a nonpolar molecule,
a dipole is induced.
When a solid produced by a chemical reaction separates from the solution it is called
a precipitate
Which of the following is at equilibrium when undissolved solute is visible?
a saturated solution
According to the kinetic-molecular theory, particles of matter
are in constant motion
The strength of London dispersion forces between molecules depends on
both the number of electrons in the molecule and the mass of the molecule.
Stirring increases the rate of dissolution because it
brings fresh solvent into contact with the solute.
The particles in both gases and liquids
can change positions with other particles
Which observation does not indicate that a chemical reaction has occurred?
change in total mass of substances
A mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together is called a(n)
chemical bond
In what kind of reaction do two or more substances combine to form a new compound?
double-displacement reaction
What is the process by which molecules of a gas randomly encounter and pass through a small opening in a container?
effusion
Which term best describes the process by which particles escape from the surface of a nonboiling liquid and enter the gas state?
evaporation
Which of these can happen due to decreasing the average energy of a liquid's particles?
freezing
The particles in a liquid are usually
have less energy than those in gas
Diffusion between two gases occurs most rapidly if the gases are at
high temperature and the molecules are small.
Raising the collision rate between solute and solvent
increases the rate of dissolution
In drawing a Lewis structure, the central atom is generally the
least electronegative atom.
After calculating the amount of reactant B required to completely react with A, then comparing that amount with the amount of B available, one can determine the
limiting reactant
A chemical reaction involving substances A and B stops when B is completely used. B is the
limiting reactant.
According to VSEPR theory, an AB2 molecule is
linear
Water in air is an example of which solute-solvent combination?
liquid-gas
The energy of the particles in a solid is
lower than the energy of the particles in liquids and gases.
The value of R, the ideal gas constant, can be calculated from measured values of a gas's pressure, volume, temperature, and
molar amount
In the chemical reaction represented by the equation wA + xB ® yC + zD, a comparison of the number of moles of A to the number of moles of C would be a(n)
mole ratio.
A neutral group of atoms held together by covalent bonds is a
molecule
To observe the effects of changing pressure on the volume of a gas, factors that must be kept constant are the gas's temperature and
moles (quantity)
According to the kinetic-molecular theory, particles of an ideal gas
neither attract or repel each other but collide
Predict what happens when zinc is added to water.
no reaction occurs
What group of elements satisfies the octet rule without forming compounds?
noble gas
Multiple covalent bonds may occur in atoms that contain carbon, nitrogen, or
oxygen
The rate of diffusion in solids is very low because the
particles are not free to move about
Iodine monochloride (ICl) has a higher boiling point than bromine (Br2) partly because iodine monochloride is a(n)
polar molecule.
A precipitate may form in a double-displacement reaction when
positive ions combine with negative ions
If the temperature of a fixed quantity and volume of gas changes, what also changes?
pressure
What does the constant bombardment of gas molecules against the inside walls of a container produce?
pressure
Which mixture is made up of the smallest particles?
salt water
Colloids
scatter light.
When sodium chlorate, NaClO3, decomposes, the products are
sodium chloride and oxygen
The kinetic-molecular theory explains the behavior of
solids, liquids, and gases.
Use VSEPR theory to predict the shape of the carbon tetraiodide molecule, CI4.
tetrahedral
Solids have a definite volume because
the particles do not have a tendency to change positions.
Which of these best describes vaporization?
the process by which a solid changes to a gas
Which of the following is an example of a nonpolar solvent?
toluene
According to VSEPR theory, the shape of an AB3 molecule is
trigonal-planar
The electrons involved in the formation of a chemical bond are called
valence electrons
Which of the following is an example of a polar solvent?
water
What happens to the volume of a gas during compression?
when compressed the volume decreases