Gas laws and Stoichiometry
Find the pressure of a gas at constant temperature and moles that has a volume of 1.32 L and pressure of 0.788 atm that is compressed to a volume of 0.890 L.
1.17 atm
How many moles of HCl are in a 250-mL sample of 6.0 M HCl?
1.5 moles of HCl
How many moles of MgCl2 are in 27.5 mL of a 3.50 M solution?
0.0963 moles of MgCl2
Name the angles and number of electron groups for each electronic geometry.
linear: 180 degrees, 2 electron groups
trigonal planar: 120 degrees, 3 electron groups
tetrahedral: 109.5 degrees, 4 electron groups
1900 mmHg
Find the volume of a gas that has a volume of 756.5 mL at 25.0 degrees Celcius that is cooled to -45.5 degrees Celcius
577.6 mL
A common light beer contains 4.2% (v/v) alcohol. What is the volume of alcohol (in ounces and in milliliters) in a 16-ounce bottle of beer?
0.672 ounces and 19.9mL
Silver and chloride ions react as shown in the following net ionic equation. Based on this reaction, how many grams of AgCl precipitate can be produced if 10.0 mL of solution containing 0.0023 M chloride ions reacts with excess Ag+ ?
Ag + (aq) + Cl − (aq) ⟶ AgCl (s)
0.0033 g AgCl
Draw Lewis structures for each of these molecules and name their electronic and molecular geometry:
N2
HNO
SCl2
1. linear with tripple bond
2. trigonal planar bent with one double bond
3. tetrahedral bent
Which intermolecular force is due to the formation
of an instantaneous (not permanent) dipole?
dispersion forces
Natural gas burns cleanly in the air, according to the equation shown below
CH4(g) + 2O2(g) → CO2(g) + 2H2O (g)
If 13.1 liters of CH4 burn at a pressure of 1.00 atmosphere and a temperature of 290 K, what mass of carbon dioxide gas is produced?
24.2g CO2
Normal saline solution is 0.90% NaCl (g/mL). How many grams of sodium chloride are needed to prepare 0.50 L of normal saline solution?
4.5g NaCl
Calcium and carbonate ions combine in a precipitation reaction, as shown in this net ionic equation. If 25.0 mL of a solution containing 0.0015 M Ca? reacts with excess carbonate, how many grams of CaCO3, will form?
Ca2+ (ag) + CO32- (aq) → CaCO3 (s)
0.0038 g CaCO3
Identify the formal charge on each of these atoms:
a. an oxygen atom having one covalent bond and three lone pairs
b. an oxygen atom having two covalent bonds and two lone pairs
c. an oxygen atom having three covalent bonds and one lone pair
a. 6-1-6= -1
b. 6-2-4= 0
c. 6-3-2= +1
Which law looks at the relationship between pressure and volume when temperature and number of gas particles is held constant?
Boyle's law
In the fermentation of glucose, how many moles of carbon dioxide are produced for each kilogram of glucose that reacts? If the reaction takes place in a sealed container and the gas occupies a volume of 8.10 liters at a temperature of 21 °C, find the pressure of the carbon dioxide gas inside the container.
C6H12O6(s) → 2C2H6O (l) + 2CO2(g)
33.1 atm CO2
Starting from a 12.0-M concentrated HCl solution, you need to prepare 180 mL of 1.0-M aq. HCl. What volume of concentrated HCl do you need?
15 mL conc. HCl
Calcium metal reacts with aqueous hydrobromic acid to produce calcium bromide and hydrogen gas, as shown in the equation below. What volume of 2.50-M aq. HBr is required to produce 200.0 L of hydrogen gas at a temperature of 298 K and a pressure of 1.20 atm?
Ca (s) + 2 HBr (aq) ⟶ CaBr2 (aq) + H2 (g)
7.85 L aq. HBr solution
Draw the lewis structures for each of these molecules. Identify any polar covalent bonds, and state whether the molecule has a net dipole. Show the direction of the net dipole.
a. Cl2
b. HCN
c. PF3
a. this bond is not polar and has no net dipole
b. the C-N bond is polar covalent
c. all P-F bonds are polar covalent
What is the relationship between intermolecular forces and surface tension?
As force the force increases, the surface tension increases (direct relationship)
Acetylene torches burn at very high temperatures, using this reaction:
2 C2H2 (9) + 5 O2 (g) → 4 CO2 (g) + 2 H2O (g)
At standard temperature and pressure, what volume of oxygen gas is required to completely react with a 4.8-liter cylinder of acetylene having an absolute pressure of 80 psi and a temperature of 20 °C?
61 L O2
(P=5.44atm, T=293K, nC2H3=1.09mol, nO2=2.73mol)
If 0.50 L of 1.0-M aq. NaNO3 solution is combined with 2.40 L of 3.2-M aq. Fe(NO3)2 solution, how many moles of nitrate are in the combined solution? What is the molarity of nitrate in the combined solution?
5.5 M
Aqueous Hydrochloric acid reacts with zinc metal according to this reaction:
2 HCl (aq) + Zn (s) --> ZnCl2 (aq) + H2 (g)
If 15.0mL of 3.4M aq. HCl reacts with excess zinc
a.)How many moles of ZnCl2 are produced?
b.)How many grams of H2 gas are produced?
c.)If the reaction takes place at standard temperature and pressure, what volume of H2 gas is produced?
a.) 0.026 mol ZnCL2
b.) 0.052g H2
c.) 0.57 L H2
The structure of aspirin is shown here. How many atoms in this molecule have a tetrahedral electronic geometry? How many atoms have a trigonal planar electronic geometry? How many polar covalent bonds are present? Show the direction of polarity of these bonds.
10 trigonal planar, 3 tetrahedral
An ideal gas is allowed to cool at a constant pressure. The gas occupies a volume of 20.0L at a temperature of 273.15 K. At what temperature will it occupy a volume of 10.0 L?
137 K