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Wize University Chemistry Textbook > Gases and their Properties

Ideal Gas Law

4 Activities

Wize University Chemistry Textbook > Stoichiometry

Stoichiometry

6 Activities

At 100oC and 1.00 atm, what volume of nitrogen gas is required to react completely with 10.0 L of hydrogen gas to produce ammonia gas?
More Ideal Gas Law Questions:
Ideal Gas Law: Kinetic Molecular Theory
The natural gas delivered to homes in Calgary is normally a mixture of methane (CH4), ethane (C2H6), propane (C3H8) and carbon dioxide (CO2).
(a) In the laboratory, a chemistry student has collected some Calgarian natural gas in a 2.00 L plastic bottle at 0.902 atm and 23°C. What is the concentration of gas in the bottle?
(b) The bottle was weighed before and after filling with gas to determine the exact composition of gases. The student found that in the mixture the mole fraction of C3H8(g) was 0.10 and the mole fraction of CH4(g) was 0.90. What was the total mass of the gas in the bottle?
Partial Pressure and Vapor Pressure
A sample of N2 gas was collected over water. The temperature of the vessel was 300.0 K and the volume of the sample was 18.0 L. The vapor pressure of water at 300.0 K is 3.53 kPa and the total pressure of the sample was 122.00 kPa. What is the mass of the N2 in this sample?
Practice: Kinetic Molecular Theory
The natural gas delivered to homes in Calgary is normally a mixture of methane (CH4), ethane (C2H6), propane (C3H8) and carbon dioxide (CO2).
(a) In the laboratory, a CHEM 203 student has collected some Calgarian natural gas in a 2.00 L plastic bottle at 0.902 atm and 23°C. What is the concentration of gas in the bottle?
(b) The bottle was weighed before and after filling with gas to determine the exact composition of gases. The student found that in the mixture the mole fraction of C3H8(g) was 0.10 and the mole fraction of CH4(g) was 0.90. What was the total mass of the gas in the bottle?
Ideal Gas Laws: Molar volume
Answer the following two questions based on the Ideal Gas Law:
Like Spring 2019 Exam 2
When 100 g of He and 100 g of Ne are placed in a container, the partial pressure of Ne is found to be 6 atm. What is the partial pressure of He?
Ideal Gas Law
If 10 g each of O2(g)\rm O_2(g) and HBr(g)\rm HBr(g) are in separate containers of equal volume and temperature, which one of the following statements is true?
Partial Pressure and Vapor Pressure
A sample of N2 gas was collected over water. The temperature of the vessel was 300.0 K and the volume of the sample was 18.0 L. The vapor pressure of water at 300.0 K is 3.53 kPa and the total pressure of the sample was 122.00 kPa. What is the mass of the N2 in this sample?
Ideal Gas Law
4 moles of O3(g) are trapped inside a sealed rigid vessel. The gas undergoes a reaction,
O3(g)→1.5 O2(g)\rm O_3(g) \rightarrow 1.5\ O_2(g)
Assuming all of the oxygen is consumed and the volume has remained constant, what was the effect on the pressure
A 10.0 L sample of Br2 gas is collected over water at 298 K. If the total pressure of the sample is 180.0 kPa, how many mols of Br2 are present in this sample? The vapor pressure of water at 298 K is 3.17 kPa. [Do NOT include units in your answers]
A mixture of 4.6 mols of H2 gas, 3.1 mols of N2 gas and 2.6 mols of He are stored in a 60.0 L canister at 298 K. What is the partial pressure of each compound?
P
H2
Find the new volume of 3.0 mols of an ideal gas initially at standard temperature and pressure after the pressure is changed to 40.0 kPa.
[Do Not include units in your answer]
Ideal vs real behaviour of gases
A sample of gas has a molar volume of 10.1 L at 745 Torr and −138 °C. Is the gas behaving ideally?
Gas Stoichiometry and Limiting Reagent
Consider the following equation:
4NH3(g) + 7O2(g) → 4NO2(g) + 6H2O(l)
3 L NH3 and 7 L O2 were reacted at 350 °C and 111 kPa. How much NO2 can be produced?
Partial Pressure
A mixture of H2(g) and CO(g) (total mass 4.50 g) occupies a volume of 3.76 L at 298 K and 108 kPa. What is the partial pressure of each gas in this mixture? Calculate the volume percent of H2?
Vapour Pressure
A sample of N2 gas was collected over water. The temperature of the vessel was 300.0 K and the volume of the sample was 18.0 L. The vapour pressure of water at 300.0 K is 3.53 kPa and the total pressure of the sample was 122.00 kPa. What is the mass of the N2 in this sample?
Gas Law
Consider the following two containers of gas that are at the same temperature. Which of the following statements comparing these two containers are false and which are true?
Gases: Vapor Pressure
A sample of N2 gas was collected over water. The temperature of the vessel was 300.0 K and the volume of the sample was 18.0 L. The vapour pressure of water at 300.0 K is 3.53 kPa and the total pressure of the sample was 122.00 kPa. What is the mass of the N2 in this sample?
Ideal Gas Law: Gas Mixtures
2. A mixture of 4.6 mols of H2 gas, 3.1 mols of N2 gas and 2.6 mols of He are stored in a 60.0 L canister at 255 K. What is the partial pressure of each compound?
P
H2
Ideal Gas Law: Gas Mixtures
3. A 10.0 L sample of Br2 gas is collected over water at 298 K. If the total pressure of the sample is 180.0 kPa, how many mols of Br2 are present in this sample? The vapor pressure of water at 298 K is 3.17 kPa.
Ideal Gas Law: Partial Pressures
Calculate the partial pressure of neon (in atm) in a mixture of 3.1 g of argon, 1.2 g of neon, and 2.4 g of krypton at 0oC in 1.5 L container.
Ideal Gas Law: Pressure
0.103 moles of Cl2 gas in a sealed cylinder with a piston has a volume of 3.25 L at a pressure of 0.780 atm. Assuming that the sample behaves as an ideal gas and the temperature remains constant, calculate the pressure (in atm) of the sample if the piston is moved and the volume of the cylinder is reduced to 1.82 L.
2 gases were mixed together in a 5 L vessel at 243 K to create a total pressure of 9.3 atm. If gas 1 has 2 moles, what is the partial pressure of gas 2? (R = 0.08206 L*atm/mole*K)
0.238 g of a gas were placed in a 250 mL vessel. If the gas is heated to 85 oC, the gas has a pressure of 7 atm. Which gas is in the vessel? (R = 0.08206 L*atm/mole*k)
Ideal Gas Law: Molecular mass calculation
The density of an unknown gas at 100oC and 746 torr is 1.994 g/L. What is the molecular mass (in g/mol) of this unknown gas?
A mixture of 4.6 moles of H2 gas, 3.1 moles of N2 gas and 2.6 moles of He are stored in a 60.0 L canister at 298 K. What is the partial pressure of each compound? (Write answer in format X.XX atm, i.e. 4.25 atm)
P
H2
3 moles of O2 gas at 100 K was released into a 2 L balloon. If O2 is a real gas, what is the pressure of the gas? (For O2, a = 0.0145 atm /L2, and b = 0.1711 L/mol, R = 0.08206 L*atm/mole*K).
An ideal gas at 30.0 C and pressure of 2 × 105 Pa is in a container having a volume of 1.40 L.
Determine the number of moles of gas in the container.
The gas pushes against a piston, expanding to twice its original volume, while the pressure falls to atmospheric pressure. Find the final temperature.
Ideal Gas Laws: Gas mixtures
2 gases were mixed together in a 5 L vessel at 243 K to create a total pressure of 9.3 atm. If gas 1 has 2 moles, what is the partial pressure of gas 2? (R = 0.08206 L*atm/mole*K)
Gas Laws: Van der Waals Equation
Find the difference between the ideal pressure and the Van der Waals pressure for 2 mol of CO2 in a 1L vessel at room temperature. CO2 (a = 3.640 L2atm/mol2; b = 0.04267 L/mol).
Ideal Gas Law
A sample of argon is loaded into a 3L sealed vessel and at room temperature the initial pressure is 2.6atm. The vessel is then loaded into an autoclave and heated to 580oC. What is the final pressure inside the vessel?
Ideal Gas Law
A 8.0 L sample of Br2 gas is collected over water at 298 K. If the total pressure of the sample is 168.0 kPa, how many moles of Br2 are present in this sample? The vapor pressure of water at 298 K is 3.17 kPa.
Ideal Gas Law: Partial Pressure
A mixture of 4.6 moles of H2 gas, 3.1 moles of N2 gas and 2.6 moles of He are stored in a 60.0 L canister at 255 K. What is the partial pressure of each compound?
P
H2
Ideal Gas Law: Mole fraction
A 10.0 L sample of Br2 gas is collected over water at 298 K. If the total pressure of the sample is 180.0 kPa, how many moles of Br2 are present in this sample? The vapor pressure of water at 298 K is 3.17 kPa.
Ideal Gas Law
A sample of a gaseous compound is distributed into two vessels, A and B, of equal volume held at the same temperature and pressure. Vessel A is heated to twice its initial temperature in Kelvin, followed by compression to one quarter of its initial volume. Vessel B is cooled to half of its initial temperature in K, followed by expansion to twice it’s original volume. What is the ratio of the pressure in vessel A to the pressure in vessel B after these transformations?
Ideal Gas Law: Volume as a function of pressure
Find the new volume of 3.0 moles of an ideal gas initially at standard temperature and pressure after the pressure is changed to 40.0 kPa.
Ideal Gas Law: Volume as a function of moles
What is the volume of 2.5 moles of Ne at 298 K and 1.0 atm? What is the new volume after 4.5 moles of Ne are added?
Ideal Gas Law: Gas mixtures
A mass of 0.4 g of hydrogen (H2) and 3.2 g of helium (He) are mixed in a rigid 500 mL container. What is the partial pressure of helium when the container is cooled to 77 K?
A 6.00 L flask is evacuated and weighed, 21.64g. The vessel is then filled with a gas at STP, after filling the vessel weighs 27.31g. What is the molecular weight of the gas?
Ideal Gas Law: Identify the Ideal Gas
A scientist has a series of tubes filled with different noble gases in her lab. She realizes one day that the labels have worn away and she can't remember which gas is which. She decides to determine the gasses identity using the ideal gas law. She finds that there is 4.314 g of gas and at room temperature (298 K) the pressure in the 2.75 L tube is 97.4 kPa. What is the identity of the gas?
Practice: Ideal Gas Law
3.0 moles of Argon are stored in a 2.0 L container kept at 10 °C. What is the pressure of this gas? Please calculate the pressure in kPa.
A sample of a gaseous compound is distributed into two vessels, A and B, of equal volume held at the same temperature and pressure. Vessel A is heated to twice its initial temperature in Kelvin, followed by compression to one quarter of its initial volume. Vessel B is cooled to half of its initial temperature in K, followed by expansion to twice it’s original volume. What is the ratio of the pressure in vessel A to the pressure in vessel B after these transformations?
A 15 L sample of N2 gas held at 328 K is compressed such that the pressure rises from 1.0 atm to 7.8 atm. What is the final volume of the gas?
For an ideal gas which variables in the following pairs are not directly proportional to each other (if all other factors remain constant)?
Find the new volume of 3.0 mols of an ideal gas initially at standard temperature and pressure after the pressure is dropped to 20.0 kPa.
When coal is burned, sulfur that is present within coal is converted to sulfur dioxide (SO2). This results in the acid rain phenomenon. If 3.75 kg of S are reacted with oxygen, calculate the volume of SO2 gas (in L) formed at 25.0 °C and 1.10 atm.
Ideal Gas Law: Stoichiometry
What volume of hydrogen (STP) is produced by dissolving one-half mole of aluminum in sulfuric acid?
2Al(s)+3H2SO4(aq)→Al2(SO4)3(aq)+3H2(g)2Al(s)+3H_2SO_4(aq)→Al_2(SO_4)_3(aq)+3H_2(g)
Ideal Gas Law: Molecular weight
At 150.°C and 1.00 atm, 500. mL of a vapor has a mass of 0.4183 g. What is the molecular weight of the compound?
Which of the following graphs is NOT consistent with the ideal gas law assuming that the other parameters are kept constant?
Ideal Gas Law: Practice
A small tank of compressed oxygen gas is left outside in the sun and its temperature increases. Assume that the amount of gas and the volume of the tank do not change.
Identify which of the four graphs below show how…
A. …the pressure (P) of the gas inside the tank changes as T increases.
Ideal Gas Law: Kinetic Molecular Theory
The natural gas delivered to homes in Calgary is normally a mixture of methane (CH4), ethane (C2H6), propane (C3H8) and carbon dioxide (CO2).
(a) In the laboratory, a chemistry student has collected some Calgarian natural gas in a 2.00 L plastic bottle at 0.902 atm and 23°C. What is the concentration of gas in the bottle?
(b) The bottle was weighed before and after filling with gas to determine the exact composition of gases. The student found that in the mixture the mole fraction of C3H8(g) was 0.10 and the mole fraction of CH4(g) was 0.90. What was the total mass of the gas in the bottle?
The enthalpy of combustion for ethanol (C2H5OH) is -1370.7 kJ/mol. Calculate q, w, ΔH and ΔU when 45g of ethanol are burned at 1atm and 298K.
Stoichiometry
The following gaseous reaction takes place at 473 K and 101.3 kPa:
N2(g)+O2(g)→NO2(g)N_{2(g)}+O_{2(g)}\to NO_{2(g)}
If 80.0 g of 02 are available to react, how many litres of N2 will be required to completely consume the oxygen supply?
Ideal Gas Laws
5. Find the new volume of 3.0 mols of an ideal gas initially at standard temperature and pressure after the pressure is changed to 40.0 kPa.
Ideal Gas Laws: Volume
6. What is the volume of 2.5 mols of Ne at 298 K and 1.0 atm? What is the new volume after 4.5 mols of Ne are added?
Worked Example
Four moles of an ideal gas originally at 323 oC and 7.3 atm underwent a complete expansion against a constant external pressure of 1 atm and did 8kJ of work. Calculate q, ΔE, ΔH.
Solve for the missing initial variable (Vi):
hint: rearrange PV=nRT to do this!
Ideal Gas law
Inflatable balloons are often used to gently lift a sunken ship from the ocean floor to the ocean surface. We want to fill two balloons (one for each side of the ship) that are approximately 100m long cylinders with a radius of 0.5m with nitrogen gas at a pressure of 1.1 atm. If we remember that the water temperature at the ocean floor is approximately 0 oC how much nitrogen will we need? Answer in moles. R=0.08206Latm/Kmol
Ideal Gas Law
1.1 mols of Argon are stored in a 2.0 L container kept at 10 °C. What is the pressure of this gas? (answer in kPa)
Practice Exam 2 (CHEM 2045 UF)
Consider two separate 1 L containers at 273 K, one filled with 2 g H2 and one filled with 2 g of O2. Which of the following will be true?
Ideal Gas Law
12 moles of Xenon are held inside a 15L flask at room temperature.
The flask is then cooled to – 100oC.The flask is then allowed to expand into a 23L but we need to keep the pressure constant. What temperature is required to keep the pressure constant as the gas expands into the new volume.
Ideal Gas Law
12 moles of Xenon are held inside a 15L flask at room temperature.
The flask is then cooled to – 100oC what is the pressure inside the flask at -100oC?
Ideal Gas Law
12 moles of Xenon are held inside a 15L flask at room temperature.
What is the initial pressure inside the flask?
Ideal Gas Law
Four grams of Helium (an ideal gas) is packed into a 500mL flask and heated in a boiling pot of water. What is the internal pressure of the flask? R=0.08206Latm/Kmol
More Stoichiometry Questions:
Consider the reaction between hydrogen gas (H2\rm H_2) and carbon monoxide (CO\rm CO) which produces methanol gas (CH3OH\rm CH_3OH).
2H2(g)+CO(g)→CH3OH(g)\rm 2H_2(g)+CO(g)\rightarrow CH_3OH(g)
The scheme above represents the initial content of a flask before any reaction took place. Which of the schemes below would correspond to the content of this flask once the reaction has reached completion?
Precipitation
A 4.23 g sample of a mixture of BaCl2 and Ba(NO3)2 is treated with excess AgNO3(aq). The precipitate is filtered off and then dried. If the dry precipitate weighs
5.27 g, what is the percentage by mass of BaCl2 in the original mixture?
Molar masses:
A piece of zinc is allowed to react with an excess quantity of sulfuric acid, and the hydrogen gas produced is collected in a gas burette by displacement of water. Neglecting the effect of the vapor pressure of water on the system, calculate how many milligram (mg) of zinc would generate 92.0 mL of the gas at a temperature of 25.0 °C and a pressure of 1.00 atm.
Stoichiometry: Mole Ratios
How many moles of H2 and N2 can be formed by the decomposition of 12.7mol of ammonia, NH3? Do not include units in your answer.
2NH3→N2+3H22NH_3\rightarrow N_2+3H_2
Stoichiometry: Limiting Reagent
What is the maximum mass of Ca(CN)2 that can be obtained from 1.56 g of HCN and 2.58 g of Ca(OH)2? The balanced chemical equation is shown below.
2HCN(aq)+Ca(OH)2(aq)→Ca(CN)2(aq)+2H2O(ℓ)27.03g/mol74.10g/mol92.12g/mol18.02g/mol \def\arraystretch{1.5}\begin{array}{ccccccc} 2 HCN(aq) &+ &Ca(OH)_2(aq)&→& Ca(CN)_2(aq) &+& 2 H_2O(\ell) \\ 27.03g/mol && 74.10g/mol && 92.12g/mol&& 18.02g/mol \end{array}
Stoichiometry
The thermite reaction is used for welding railroad rails. The reaction is:
Fe3O3(s)+2Al(s)→3Fe(s)+Al2O3(s){Fe}_3{O}_3({s})+2{Al(s)}\rightarrow 3{Fe(s)}+{Al}_2{O}_3\text{(s)}
If 25g of iron, Fe(s), are produced from a reaction how many grams of aluminum oxide are generated?
Stoichiometry: Yield
What is the maximum amount of iodine gas (in moles) that can be formed if 1.00 mole of manganese (IV) oxide was allowed to react with 2.00 moles of hydroiodic acid to from manganese(II) iodide, iodine gas, and water?
Gases (Ideal) IIII
Today, most ammonia is produced by the Haber Process, which combines nitrogen from the air with hydrogen to produce ammonia gas. At 400oC and 2.00 atm, what volume of nitrogen gas is required to react completely with 50.0 L of hydrogen gas to produce ammonia gas?
Precipitation
Given the following reaction:
Na2SO4(s) + 2 C(s) → Na2S(s) + 2 CO2(g)
How many grams of carbon are required to produce 18.4 g Na2S(s)?
Limiting Reagent
What is the maximum mass of Ca(CN)2 that can be obtained from 1.56 g of HCN and 2.58 g of Ca(OH)2? The balanced chemical equation is shown below. The molar masses are given in gmol−1. (Choose the closest answer.)
2 HCN(aq) + Ca(OH)2(aq) → Ca(CN)2(aq) + 2 H2O(l)
27.03 74.10 92.12 18.02
Precipitation
A 4.23 g sample of a mixture of BaCl2 and Ba(NO3)2 is treated with excess AgNO3(aq). The precipitate is filtered off and then dried. If the dry precipitate weighs
5.27 g, what is the percentage by mass of BaCl2 in the original mixture?
Molar masses:
Stoichiometry
How many moles of H2 and N2 can be formed by the decomposition of 12.7 mol of ammonia, NH3?
When coal is burned, sulfur that is present within coal is converted to sulfur dioxide(SO)2{\small \text{(SO)}_2}. This results in the acid ran phenomenon.
S(s)+O2(g)→SO2(g)\text{S(s)}+\text{O}_2\text{(g)}\rightarrow\text{SO}_2\text{(g)}
If 3.75 kg of S are reacted with oxygen, calculate the volume ofSO2{\small \text{SO}_2} gas (in L) formed at 25.0°C{\small \degree\text{C}} and 1.10 atm.
The following gaseous reaction takes place at 473 K and 101.3 kPa:
N2(g)+O2(g)→NO2(g)N_{2(g)}+O_{2(g)}\to NO_{2(g)}
If 80.0 g of 02 are available to react, how many litres of N2 will be required to completely consume the oxygen supply?
Br2 and F2 can react to form BrF5(g) according to the following unbalanced reaction: R=0.08206atmL/molK
Br2(g)+ F2(g)→BrF5(g)Br_{2\left(g\right)}+\ F_{2\left(g\right)}\to BrF_{5\left(g\right)}
How many litres of BrF5 can be produced at 43 °C and 1.0 atm if 18 mols of F2 are reacted with an excess quantity of Br2?
Stoichiometry 3
What mass of C5H12 produces 9.033 ⋅\cdot 1022 CO2 molecules upon complete combustion?
What volume of 3.16 M H3PO4 solution is necessary to react with 27 mL of 0.18 M Mg(OH)2?
Consider the two following reactions:
CS2 + 3Cl2 → CCl4 (l)+ S2Cl2 (l) 60% yield
3 CCl4 (l) + 2 SbF3 (s) → 3 CCl2F2 (g) + 2SbCl3 (s) 80% yield
Redox Reactions and Calculation Using the Mole Method
Cu2+ reacts with Na2S2O3 by the following reaction:
Cu2+ + I− + S2O32− → CuI (s) + S4O62−
A 4.115 g sample containing CuSO4 and excess KI is treated with 32.55 mL of 0.2214 M Na2S2O3 solution to titrate Cu2+. What is the % CuSO4 in the sample?
Sulfur, S8, reacts with O2 at high temperature to produce SO2. If 160 molecules of O2 are used up:
a. How many molecules of sulfur react?
b. How many molecules of SO2 form?
Consider the following two step reaction:
TeO2 + 2 OH- = TeO32- + H20
TeO32- + 2H+ = H2TeO3
What mass of KClO3 is required to produce proper amount of O2 needed to achieve complete combustion of 78.88 g CH4?
2 KClO3 → 2 KCl + 3 O2
Gas Stoichiometry
The oxidation of phosphine is shown below:
2 PH3(g) + 3 O2(g) → P2O3(s) + 3 H2O(g)
What volume of O2(g), measured at 101 kPa and 50 oC, is consumed in the formation of 20.0 g of P2O3 by this reaction?
Mole method
What is the maximum number of moles of CCl2F2 that can be obtained from 6.5 mol SbF3 and 5.2 mol CCl4?
3 CCl4 + 2 SbF3 → 3 CCl2F2 + 2 SbCl3
Gas Stoichiometry
A 1.8 g mixture of KClO3 and KCl was heated until the complete decomposition of KClO3. The released O2 has a volume of 405 mL at 25 ⁰C and 745 Torr. What was the percent of KClO3 present in the mixture?
Calculating Molarity from Mass
In a reaction described by the equation below (unbalanced), excess calcium carbonate is added to 70.0 mL of hydrochloric acid. The theoretical yield of this reaction produces 20.0 g of carbon dioxide. Assuming the reaction proceeds with 100% yield and the volume of the solution does not change upon addition of solid, calculate the molairty, in mol/L, of the hydrochloric acid solution. The units for your answer should be in M or mol/L, but no units are required in your answer.
CaCO3 (s)    +    HCl (aq)    →    CaCl2 (aq)    +    CO2 (g)    +    H2O (l)CaCO_3\ \left(s\right)\ \ \ \ +\ \ \ \ HCl\ \left(aq\right)\ \ \ \ \rightarrow\ \ \ \ CaCl_2\ \left(aq\right)\ \ \ \ +\ \ \ \ CO_2\ \left(g\right)\ \ \ \ +\ \ \ \ H_2O\ \left(l\right)
Chemical Reactions: Limiting Reagent
Based on the unbalanced chemical reaction below:
NaNO2 (s)    +    O2 (g)    →    NaNO3 (s)NaNO_2\ \left(s\right)\ \ \ \ +\ \ \ \ O_2\ \left(g\right)\ \ \ \ \rightarrow\ \ \ \ NaNO_3\ \left(s\right)
a) Calculate the mass of sodium nitrate if 10.25 g of sodium nitrite is reacted with 7.55 g of oxygen gas.
Chemical Reactions: Limiting Reagent & Percent Yield Practice
Iron oxidizes when exposed to oxygen to form iron oxide according to the following equation:
Fe + O2 ​→Fe2​O3​
352g of pure iron is exposed to 12.0 mols of O2, and after a period of time 46.7 g of iron oxide (rust) is collected.
What volume of hydrogen (STP) is produced by dissolving one-half mole of aluminum in sulfuric acid?
2Al(s)+3H2SO4(aq)→Al2(SO4)3(aq)+3H2(g)2Al_{(s)}+3H_2SO_{4(aq)} \to Al_2(SO_4)_{3(aq)}+3H_{2(g)}
Br2 and F2 can react to form BrF5(g) according to the following unbalanced reaction:
Br2(g)+ F2(g)→BrF5(g)Br_{2\left(g\right)}+\ F_{2\left(g\right)}\to BrF_{5\left(g\right)}
How many litres of BrF5 can be produced at 43 °C and 1.0 atm if 18 mols of F2 are reacted with an excess quantity of Br2?
Stoichiometry: Limiting reagents
Ammonia, NH3, and borane, BH3, react to form a Lewis adduct, ammonia borane as shown below.
NH3(sol)+BH3(sol)→NH3BH3(s)NH_{3(sol)} + BH_{3(sol)} \rightarrow NH_3BH_{3(s)}
If 24 mL of a 0.74 M solution of ammonia is mixed with 12 mL of a 1.8 M solution of borane what is the maximum mass of ammonia borane that can be produced?
Stoichiometry: Mass Percentage
How many grams of PCl3 are needed to produce 10g of POCl3 using an excess of hydrogen peroxide assuming a typical reaction yield of 78%?
PCl3+H2O2→POCl3+H2OPCl_3+H_2O_2\rightarrow POCl_3+H_2O
Stoichiometry: Percent yield
Consider the following unbalanced reaction:
C4H8O2+O2→CO2+H2O\rm C_4H_8O_2 +O_2 \to CO_2 + H_2O
If 36.00 g of C4H8O2\rm C_4H_8O_2 is burned, what mass of water would be collected if the reaction yield was 76%?
Chemical Reactions: Limiting Reagent
15mL of a 1.2M solution of HCl reacts with 22mL of a 1.4M solution of NaOH. How many moles of NaOH are left after the reaction is complete?
HCl(aq)+NaOH(aq)→H2O(l)+NaCl(aq)HCl_{(aq)}+NaOH_{(aq)}\rightarrow H_2O_{(l)}+ NaCl_{(aq)}
Stoichiometry: Mass of product calculation
16.0 mL of Hg (mp = -38.8oC, density = 13.56 g/mL) reacts with Fluorine gas and the reaction goes to completion as shown below in the unbalanced chemical reaction.
Hg(l)+F2(g)→HgF2(s)Hg_{(l)}+F_{2(g)}\rightarrow HgF_{2(s)}
Once the reaction has gone to completion, what mass of Mercury Fluoride, HgF2, is produced?
Chemical Reactions: Hydrate Question
A 15.67 g sample of a hydrate of magnesium carbonate (MgCO3) was heated, without decomposing the carbonate, to drive off the water. The mass was reduced to 7.58 g. What is the formula of the hydrate?
Practice: Mass Percentage
A compound containing sodium, chlorine, and oxygen is 25.42% sodium by mass. A 3.25 g sample gives 4.33 x 1022 atoms of oxygen. What is the empirical formula?
Hint: This is a tricky problem but start by writing the variables that you know.....what can you solve for?
If you're still not sure, my hint is to start with O! We can calculate moles of O, then mass of O, then % mass of O! What should we do next??
Stoichiometry: Percent Yield
A compound with the formula C7H8O3\text{C}_7\text{H}_8\text{O}_3 is burned to completion in excess O2\text{O}_2. If 18.0g of the organic compound was consumed in the reaction, how many grams of H2O\text{H}_2\text{O} will be collected if the yield was 85%?
In dilute nitric acid, HNO3, copper metal dissolves according to the following equation. How many grams of HNO3 are needed to dissolve 11.45 g of Cu according to this equation?
3Cu+8HNO3→3Cu(NO3)2+2NO+4H2O3Cu+8HNO_3→3Cu(NO_3)_2+2NO+4H_2O
When coal is burned, sulfur that is present within coal is converted to sulfur dioxide (SO2). This results in the acid rain phenomenon. If 3.75 kg of S are reacted with oxygen, calculate the volume of SO2 gas (in L) formed at 25.0 °C and 1.10 atm.
The potassium salt of benzoic acid, potassium benzoate (KC7H5O2, MM=160 g/mol) can be made by the action of potassium permanganate on toluene (C7H8, MM=92 g/mol). If the yield of potassium benzoate cannot realistically be expected to be more than 71%, what is the minimum number of grams of toluene needed to produce 11.5 g of potassium benzoate?
C7H8+2KMnO4→KC7H5O2+2MnO2+KOH+H2OC_7 H_8+2KMnO_4→KC_7 H_5 O_2+2MnO_2+KOH+H_2 O
Stoichiometry: Percent Yield
How many grams of PCl3 are needed to produce 10g of OPCl3 using an excess of hydrogen peroxide assuming a typical reaction yield of 78%?
PCl3​ + H2​O2 ​→ OPCl3​ + H2​O
Stoichiometry
The thermite reaction is used for welding railroad rails. The reaction is:
Fe3O3(s)+2Al(s)→3Fe(s)+Al2O3(s)\text{Fe}_3\text{O}_3\text({s})+2\text{Al(s)}\rightarrow 3\text{Fe(s)}+\text{Al}_2\text{O}_3\text{(s)}
If 25. grams of iron, Fe(s), are produced from a reaction how many grams of aluminum oxide are generated?
Chemical Reactions: Limiting Reagent & Percent Yield Practice
Iron oxidizes when exposed to oxygen to form iron oxide according to the following equation:
Fe + O2 ​→Fe2​O3​
352g of pure iron is exposed to 12.0 mols of O2, and after a period of time 46.7 g of iron oxide (rust) is collected.
Stoichiometry and Ideal Gas Law Practice
The combustion of methanol (CH3OH) is shown below. If 16g of methanol is burned in oxygen, what volume of CO2 is produced if the pressure is 101.3kPa, T=25C, and R=8.314kPaL/molK? Round to the nearest whole number.
CH3OH + O2 --> CO2 + H2O
Is the equation balanced?
No
A piece of zinc is allowed to react with an excess quantity of sulfuric acid, and the hydrogen gas produced is collected in a gas burette by displacement of water. Neglecting the effect of the vapor pressure of water on the system, calculate how many milligram (mg) of zinc would generate 92.0 mL of the gas at a temperature of 25.0 °C and a pressure of 1.00 atm.
Consider the reaction between hydrogen gas (H2\rm H_2) and carbon monoxide (CO\rm CO) which produces methanol gas (CH3OH\rm CH_3OH).
2H2(g)+CO(g)→CH3OH(g)\rm 2H_2(g)+CO(g)\rightarrow CH_3OH(g)
The scheme above represents the initial content of a flask before any reaction took place. Which of the schemes below would correspond to the content of this flask once the reaction has reached completion?
A 2.56 g sample of ZnSO4 ⋅ 7H2O is heated to dryness. Determine the anhydrous mass remaining after all the water has been driven off. (provide an answer with 2 decimal places and correct unit)
Stoichiometry: Molar mass and Avogadro's Number
How many hydrogen atoms are in exactly 2 g of hydrazinium sulfate, N2H6SO4?
Ideal Gas Law: Stoichiometry
What volume of hydrogen (STP) is produced by dissolving one-half mole of aluminum in sulfuric acid?
2Al(s)+3H2SO4(aq)→Al2(SO4)3(aq)+3H2(g)2Al(s)+3H_2SO_4(aq)→Al_2(SO_4)_3(aq)+3H_2(g)
A piece of zinc is allowed to react with an excess quantity of sulfuric acid, and the hydrogen gas produced is collected in a gas burette by displacement of water. Neglecting the effect of the vapor pressure of water on the system, calculate how many milligram (mg) of zinc would generate 92.0 mL of the gas at a temperature of 25.0 °C and a pressure of 1.00 atm.
Gas Laws: Practice
A student decides to do a more controlled version of the hydrogen balloon explosion. The unbalanced chemical equation for this reaction is shown below:
H2(g)+O2(g)→H2O(g)H_2(g)+O_2(g)→H_2O(g)
(a) Write the balanced chemical equation for this reaction.
Chemical Reactions: Limiting Reagent
Potassium carbonate, K2CO3, will react with acetic acid, CH3CO2H, to produce carbon dioxide gas, as per the following unbalanced reaction:
K2CO3(s)+CH3CO2H(aq)→KCH3CO2(aq)+CO2(g)+H2O(l)K_2CO_3(s)+CH_3CO_2H(aq)\rightarrow KCH_3CO_2(aq)+CO_2(g)+H_2O(l)
If 4 moles of K2CO3 reacted with an excess of CH3CO2H, how many moles of CH3CO2H reacted?
Stoichiometry
Br2 and F2 can react to form BrF5(g) according to the following unbalanced reaction: R=0.08206atmL/molK
Br2(g)+ F2(g)→BrF5(g)Br_{2\left(g\right)}+\ F_{2\left(g\right)}\to BrF_{5\left(g\right)}
How many litres of BrF5 can be produced at 43 °C and 1.0 atm if 18 mols of F2 are reacted with an excess quantity of Br2?
Stoichiometry
The following gaseous reaction takes place at 473 K and 101.3 kPa:
N2(g)+O2(g)→NO2(g)N_{2(g)}+O_{2(g)}\to NO_{2(g)}
If 80.0 g of 02 are available to react, how many litres of N2 will be required to completely consume the oxygen supply?