ALL hmwk
The atmospheric pressure at the summit of Mount McKinley is 532 mmHg on a certain day. What is the pressure in atmospheres and in kilopascals?
0.7 atm 70.92 kPa
Label the energy diagrams below and complete the statements about each.
see pic
SI units for: Length Volume Mass Time Temperature
Length: meter Volume: m^3 Mass: kilograms Time: seconds Temperature: K
Consider the following gaseous sample in a cylinder fitted with a movable piston. Initially there are n moles of the gas at temperature T, pressure P, and volume V. Choose the cylinder that correctly represents the gas after each of the following changes. (1) The pressure on the piston is tripled at constant n and T. (2) The absolute temperature is doubled at constant n and P. (3) At constant T and P, n more moles of the gas are added. (4) Absolute temperature is halved at constant P.
(1) b (2) a (3) c (4) b see pic
Methanol, ethanol, and n−propanol are three common alcohols. When 1.00 g of each of these alcohols is burned in air, heat is liberated as indicated. Calculate the heats of combustion of these alcohols in kJ/mol. (a) methanol (CH3OH), −22.6 kJ (b) ethanol (C2H5OH), −29.7 kJ Enter your answer in scientific notation. (c) n−propanol (C3H7OH), −33.4 kJ Enter your answer in scientific notation.
(a) -724 kJ (b) -1.37 × 10^3 kJ/mol (c) -2.01 × 10^3 kJ/mol
Calculate ΔHo for the reaction H2(g) + I2(g) → 2HI(g) (a) Using the equation ΔH°rxn = ∑(BE(reactants)) − ∑(BE(products)) (b) Using the equation ΔH°rxn = ∑(nΔH°f(products)) − ∑(mΔH°f(reactants))
(a) -9.2 kJ/mol (b) -9.2 kJ/mol see pic
A sample of nitrogen gas expands in volume from 2.2 to 3.7 L at constant temperature. Calculate the work done in joules if the gas expands (a) against a vacuum (b) against a constant pressure of 0.72 atm (c) against a constant pressure of 6.1 atm
(a) 0 (b) -1.09404 × 10^2 (c) -9.26895 × 10^2
Determine the number of moles of each gas present in a mixture of CH4 and C2H6 in a 2.00-L vessel at 25°C and 1.48 atm, given that the partial pressure of CH4 is 0.45 atm. (a) What is the number of moles of CH4? (b) What is the number of moles of C2H6?
(a) 0.037 mol (b) 0.085 mol
Write the numbers represented by the following prefixes: (a) 1 g = ______×10 ______ megagrams (b) 1 g = ______×10 ______ kilograms (c) 1 g = ______× 10 ______ decigrams (d) 1 g = ______×10 _______ centigrams (e) 1 g = ______× 10 _______ milligrams (f) 1 g = ______× 10 _______ micrograms (g) 1 g = ______×10 _______ nanograms (h) 1 g = ______× 10 _______ picograms
(a) 1 g = 1 ×10 -6 megagrams (b) 1 g = 1 ×10 -3 kilograms (c) 1 g = 1 × 10 1 decigrams (d) 1 g = 1 ×10 2 centigrams (e) 1 g = 1 × 10 3 milligrams (f) 1 g = 1 × 10 6 micrograms (g) 1 g = 1 ×10 9 nanograms (h) 1 g = 1 × 10 12 picograms
Calculate the mass of each of the following: (a) a sphere of gold with a radius of 11.5 cm. (The volume of a sphere with a radius r is V = (4/3)πr^3; the density of gold is 19.3 g/cm^3.) Enter in scientific notation (b) a cube of platinum of edge length 0.050 mm (density = 21.4 g/cm^3) Enter in scientific notation (c) 64.7 mL of ethanol (density = 0.798 g/mL)
(a) 1.229530876 × 10^5 (b) 2.675 × 10^5 (or 2.7 × 10^5 ?) (c) 51.6306
Express the answers to the following calculations in scientific notation, using the correct number of significant figures: (a) 145.75 + (2.3 × 10^−1) (b) 79,500 / (2.5 × 10^2) (c) (7.0 × 10^−3) − (8.0 × 10^−4) (d) (1.0 × 10^4) × (9.9 × 10^6)
(a) 1.4598 × 10^2 (b) 3.2 × 10^2 (c) 6.2 × 10^-3 (d) 9.9 × 10^10
What is the mass of the solid NH4Cl formed when 76.5 g of NH3 is mixed with an equal mass of HCl? What is the volume of the gas remaining, measured at 14.0°C and 752 mmHg? What gas is it? NH3(g) + HCl(g) → NH4Cl(s) (a) What is the mass of the NH4Cl produced? (b) Which gas remains? (c) What is the volume of the gas remaining?
(a) 112 g (b) NH3 (c) 57.0 L
Carry out the following operations as if they were calculations of experimental results and express each answer in standard notation with the correct number of significant figures and with the correct units. Enter both the answer and the units in the answer field: (a) 7.7129 m + 0.6 m + 4.33 m (b) 3.70 g − 4.2433 g (c) 4.51 cm × 7.9672 cm
(a) 12.6 m (b) -0.54 g (c) 35.9 cm^2
Perform the following arithmetic operations, and report the result to the proper number of significant figures: (a) 185.5 L + 13.65 L (b) 88.058 m − 0.45 m (c) (6.963 × 10^21 atoms) + (3.194 × 10^19 atoms)
(a) 199.2 L (b) 87.61 m (c) 6.995 × 10^21 atoms
Express the following numbers in scientific notation. Make sure you use the correct number of significant figures: (a) 0.000000027 (b) 356 (c) 47,764 (d) 0.096
(a) 2.7 × 10^-8 (b) 3.56 × 10^2 (c) 4.7764 × 10^4 (d) 9.6 × 10^-2
Perform the following arithmetic operations, and report the results to the proper number of significant figures: (a) 1.2362 cm × 2.328 cm × 10.099 cm (b) 19.0 kg/0.026 m^3 (Enter your answer in scientific notation.) (c) 1.135 × 10^10 kg − 1.080 × 10^9 kg (Enter your answer in scientific notation.) (d) 30.25 mL + 11.00 mL (e) 66 cm^3 + 180.5 cm^3
(a) 29.06 cm^3 (b) 7.3 × 10^2 kg/m^3 (c) 1.027 × 10^10 kg (d) 41.25 mL (e) 247 cm^3
The phase diagram of sulfur is shown at right. (a) How many triple points are there? (b) Which is the more stable allotrope under ordinary atmospheric conditions? (c) Describe the progression of sulfur through its various phases when it is heated at 1 atm from 80°C to 200°C.
(a) 3 (b) rhombic (c) rhombic, monoclinic, liquid, vapor see pic
Carry out the following conversions [scientific notation]: (a) 279 amu to grams (b) 105 amu to kilograms (c) 1.59 Å to meters (d) 2.07 Å to nanometers
(a) 4.632907157 × 10^-22 g (b) 1.743567209 × 10^-25 kg (c) 1.59 × 10^-10 m (d) 2.07 × 10^-1 nm
Carry out the following conversions (provide the answer for part (b) in scientific notation): (a) 52.4 m to dm (b) 50.0 mg to kg (c) 709 mL to L (d) 60.9 kg/m^3 to g/m^3
(a) 524 dm (b) 5.00 × 10^-5 kg (c) 0.709 L (d) 0.0609 m^3
Carry out the following conversions [scientific notation]: (a) 733 nm to meters (b) 2.00 billion years to seconds (assume 365 days in a year) (c) 10.0 cm^3 to cubic meters (d) 37.9 m^3 to liters
(a) 7.33 × 10^-7 m (b) 6.3072 × 10^16 s (c) 1 × 10^-5 m^3 (d) 3.79 × 10^4 L
Carry out the following conversions [scientific notation]: (a) 1.33 light-years to miles (a light-year is an astronomical measure of the distance traveled by light in a year, or 365 days; the speed of light is 3.00 × 10^8 m/s) (b) 33.5 yd to centimeters (c) 3.1 × 10^10 cm/s to ft/s
(a) 7.8186 × 10^12 mi (b) 3.06324 × 10^3 cm (c) 1.0170603674541 × 10^9 ft/s
Predict the value of ΔH°f (greater than, less than, or equal to zero) for these elements at 25°C: (a) Br2(l) (b) Br2(g)
(a) = 0 (b) > 0
Propane (C3H8) burns in oxygen to produce carbon dioxide gas and water vapor. (a) Write a balanced equation for this reaction. Include all reaction states. (b) Calculate the number of liters of carbon dioxide measured at STP that could be produced from 7.05 g of propane.
(a) C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(g) (b) 10.74 L
Label and complete each of the gas laws: (a) ____________ : at constant ____________ , the ____________ occupied by a fixed amount of gas is ____________ proportional to its absolute ____________ . (b) ____________ : at fixed ____________ and pressure, the ____________ occupied by a gas is ____________ proportional to the ____________ . (c) ____________ : at fixed ____________ and pressure, the ____________ occupied by a gas is ____________ proportional to the ____________ .
(a) Charles's law, pressure, volume, directly, temperature (b) Avogadro's law, temperature, volume, directly, number of moles (c) Boyle's law, temperature, volume, inversely, pressure
If all other factors are kept constant, identify how each change will affect the rate of evaporation. (a) Temperature Increasing the temperature of the liquid will ____ the rate of evaporation. (b) Surface area By placing a liquid into a container that exposes a greater surface area of the liquid to air, the rate of evaporation will ____. (c) Intermolecular forces A liquid with a ____ intermolecular force implies a high vapor pressure and will have a ____ rate of evaporation.
(a) increase (b) increase (c) weaker, more rapid
Based on the information given in the following figure, determine the stable phase of CO2 under each set of conditions below. (a) At 1 atm and −88°C (b) At 4.5 atm and −54°C
(a) solid (b) gas see pic
Select the correct definition for each of the following terms: (a) law of conservation of energy (b) thermochemistry (c) potential energy (d) endothermic process (e) exothermic process
(a) states that energy cannot be created or destroyed, but it can be changed from one form to another (b) the study of the heat associated with chemical reactions and physical processes (c) energy possessed by virtue of position (d) a process in which heat is absorbed from the surroundings, so the energy of the system increases (e) a process in which heat is released to the surroundings, so the energy of the system decreases
Select the correct definition for each of the following terms: (a) system (b) surroundings (c) thermal energy (d) chemical energy
(a) the portion of the universe that is singled out for study (b) everything that lies outside the system being studied (c) energy associated with the random motions of atoms and molecules (d) energy stored within the structural units of chemical substances
Calculate the heats of combustion for the following reactions. Use the standard enthalpies of formation. (a) C2H4(g) + 3O2(g) → 2CO2(g) + 2H2O(l) (b) 2H2S(g) + 3O2(g) → 2H2O(l) + 2SO2(g)
(a) −1410.9 kJ/mol (b) −1124.1 kJ/mol
A sample of water shows the following behavior as it is heated at a constant rate. If twice the mass of water has the same amount of heat transferred to it, which of the following graphs best describes the temperature variation? Note that the scales for all the graphs are the same.
(d) see pic
Identify the phase diagram of a substance using the following experimental data.
(d) see pic
From these data, S(rhombic) + O2(g) → SO2(g) ΔH∘rxn = −296.06 kJ/mol S(monoclinic) + O2(g) → SO2(g) ΔH∘rxn = −296.36 kJ/mol calculate the enthalpy change for the transformation S(rhombic) → S(monoclinic) (Monoclinic and rhombic are different allotropic forms of elemental sulfur.)
+0.3 kJ/mol
Methanol (CH3OH) is an organic solvent and is also used as a fuel in some automobile engines. From the following data, calculate the standard enthalpy of formation of methanol 2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(l) , ΔH°rxn = −1452.8 kJ/mol
-238.7 kJ/mol
According to the website of the National Aeronautics and Space Administration (NASA), the average temperature of the universe is 2.7 K. Convert this temperature to °C
-270.45 °C
Use the bond enthalpies given below to estimate the enthalpy of reaction for the combination of carbon monoxide and oxygen to produce carbon dioxide: 2CO(g) + O2(g) → 2CO2(g)
-557.3 kJ/mol see pic
Given that 2Al(s) + 3/2 O2(g) → Al2O3(s) [ΔH∘rxn = −1601 kJ/mol] and 2Fe(s) + 3/2 O2(g) → Fe2O3(s) [ΔH∘rxn = −821 kJ/mol] Calculate the standard enthalpy change for the following reaction: 2Al(s) + Fe2O3(s) → 2Fe(s) + Al2O3(s)
-7.8 × 10^2 kJ
A gas company in Massachusetts charges $1.30 for 21.5 ft3 of natural gas. Convert this rate to dollars per liter of gas
0.0021353132 dollars/L (convert ft^3 to in^3 to cm^3 to mL to L, then dollars/L)
Carry out the following operation as if it were a calculation of real experimental results. Express the answer in the correct units with the correct number of significant figures (7.85 × 10^−3 mg) − ( 9.05 × 10^−5 mg)
0.00776 mg
The volume of a sample of pure HCl gas was 263 mL at 23°C and 167 mmHg. It was completely dissolved in about 40 mL of water and titrated with an NaOH solution; 11.9 mL of the NaOH solution was required to neutralize the HCl. Calculate the molarity of the NaOH solution.
0.1999753998 M
An empty container with a volume of 150.0 cm^3 is weighed and found to have a mass of 73.5 g. The container is filled with a liquid and reweighed. The mass of the container and the liquid is 196.1 g. What is the density of the liquid to the appropriate number of significant figures
0.8173 g/cm^3
Classify each of the following values by the number of significant figures present in each: 1.2 years, 50. cm, 0.6258 mg, 670.90 in, 90 m, 12 mL, 0.005 L, 2.99 × 10^8 m/s, 2.205 lb, 3270 ft, 4 × 10^6 s, 7.0 m^2, 8.314 J/mol*K, 40.7 g, 6.022 × 10^23 mol^-1
1 sig fig: 90 m, 0.005 L, 4 × 10^6 s 2 sig figs: 12 mL, 1.2 years, 50. cm, 7.0 m^2 3 sig figs: 40.7 g, 3270 ft, 2.99 × 10^8 m/s 4 sig figs: 0.6258 mg, 6.022 × 10^23 mol^-1, 2.205 lb, 8.314 J/mol-K 5 sig figs: 670.90 in
Calculate the density of air at exactly 15°C and 1.00 atm. (Assume that air is 80.0 percent N2 and 20.0 percent O2.)
1.2185 g/L
What pressure (in atm) is exerted by a column of mercury 1.10 m high? The density of mercury is 13.5951 g/cm3.
1.448 atm
At what pressure would a sample of gas occupy 7.06 L if it occupies 3.04 L at 3.71 atm? (Assume constant temperature.)
1.60 atm
A 6.0−ft person weighs 162 lb. Express this person's height in meters and weight in kilograms(1 lb = 453.6 g; 1 m = 3.28 ft)
1.83 m 73.48 kg
The vapor pressure of a liquid doubles when the temperature is raised from 8.0 × 10^1°C to 88°C. At what temperature will the vapor pressure be six times the value at 8.0 × 10^1°C?
101°C I'm lost on this problem, my correct answer was just a guess
The density of an element is 10.5 g/cm3. What is its density in kg/m3
10500 kg/m^3
Calculate the amount of energy (in kJ) necessary to convert 377 g of liquid water from 0°C to water vapor at 172°C. The molar heat of vaporization (Hvap) of water is 40.79 kJ/mol. The specific heat for water is 4.184 J/g × °C, and for steam is 1.99 J/g × °C. (Assume that the specific heat values do not change over the range of temperatures in the problem.)
1066 kJ
Sodium peroxide (Na2O2) is used to remove carbon dioxide from (and add oxygen to) the air supply in spacecrafts. It works by reacting with CO2 in the air to produce sodium carbonate (Na2CO3) and O2. 2 Na2O2(s) + 2 CO2(g) → 2 Na2CO3(s) + O2(g) What volume (in liters) of CO2 can be consumed at STP by 415 g Na2O2?
119.17 L
What pressure (in atm and in bars) is exerted by a column of methanol (CH3OH) 159 m high? The density of methanol is 0.787 g/cm3.
12.27 bars 12.11 atm
What is the volume of 4.87 moles of an ideal gas at 27.5°C and 1.00 atm?
120.08 L
Calculate the density of a solid substance if a cube measuring 2.04 cm on one side has a mass of 113 g Calculate the mass of a cube of the same substance measuring 8.23 cm on one side
13.31 m^3 7419.53 g
Determine the amount of heat (in kJ) given off when 1.66 × 10^4 g of NO2 is produced according to the following equation: 2 NO(g) + O2(g) → 2NO2(g) ΔH = −114.6 kJ/mol
2.067535403 × 10^4
Ozone molecules in the stratosphere absorb much of the harmful radiation from the sun. How many ozone molecules are present in 4.00 L of air under the stratospheric ozone conditions of 229 K temperature and 1.79 × 10^−3 atm pressure?
2.293 × 10^20 molecules
Calculate the volume of a sample of gas at 5.65 atm if it occupies 5.64 L at 2.59 atm. (Assume constant temperature.) Use Boyle's Law to find the unknown final volume
2.59 L
If the average speed of a helium atom at a certain temperature is 1170 m/s, what is the speed in miles per hour? (1 mi = 1609 m)
2.617215 × 10^3 mi/h
When coal is burned, the sulfur present in coal is converted to sulfur dioxide (SO2), which is responsible for the acid rain phenomenon: S(s) + O2(g) → SO2(g) If 3.25 kg of S reacts with oxygen, calculate the volume of SO2 gas (in mL) formed at 30.5°C and 1.04 atm.
2427045.726 mL
At 850°C, CaCO3 undergoes substantial decomposition to yield CaO and CO2. Assuming that the H°f values of the reactant and products are the same at 850°C as they are at 25°C, calculate the enthalpy change (in kJ) if 61.70 g of CO2 is produced in one reaction.
250 kJ
A sample of gas originally occupies 26.50 L at 0.00°C. What is its new volume when it is heated to 17.00°C? (Assume constant pressure.)
28.15 L
Sodium peroxide (Na2O2) is used to remove carbon dioxide from (and add oxygen to) the air supply in spacecrafts. It works by reacting with CO2 in the air to produce sodium carbonate (Na2CO3) and O2. 2Na2O2(s) + 2CO2(g) → 2Na2CO3(s) + O2(g) What mass (in grams) of Na2O2 is necessary to consume 1.00 L CO2 at STP?
3.48 g
For the reaction O(g) + O2(g) → O3(g) ΔH° = −107.2 kJ/mol Given that the bond enthalpy in O2(g) is 498.7 kJ/mol, calculate the average bond enthalpy in O3.
303.0 kJ/mol
The vapor pressure of ethanol is 1.00 × 10^2 mmHg at 34.90°C. What is its vapor pressure at 60.5°C? (ΔHvap for ethanol is 39.3 kJ/mol.)
325 mmHg
Using the following chemical equation and the following data determine the P―Cl bond enthalpy: PH3(g) + 3HCl(g) → PCl3(g) + 3H2(g)
328.3 kJ/mol see pic
What volume (in liters) of water vapor will be produced when 38 L of H2 and 19 L of O2 react according to the equation given below? (Assume that the reactants and product are all at the same temperature and pressure.) 2 H2(g) + O2(g) → 2 H2O(g)
38 L
From the following data, calculate the average bond enthalpy for the N-H bond: NH3(g) → NH2(g) + H(g), ΔH° = 435 kJ/mol NH2(g) → NH(g) + H(g), ΔH° = 381 kJ/mol NH(g) → N(g) + H(g), ΔH° = 3.60 × 10^2 kJ/mol
392 kJ/mol
statements represents an exact number
4 dozen eggs were used to make a breakfast 50,871 tickets were sold at a sporting event
Determine the molar mass of a gas with a density of 1.5187 g/L at 80.00°C and exactly 1 atm.
44.03 g/mol
At what temperature (in °C) would 1.00 mole of ideal gas occupy 60.0 L (P = 1.00 atm)?
457.05 °C
At one spot on Venus, the second closest planet to the sun, the surface temperature was 751 K. Convert this temperature to °C and °F
477.85 °C 892.13 °F
At what temperature (in °C) will a sample of gas occupy 92.3 L if it occupies 45.0 L at 95.0°C? (Assume constant pressure.) Use Charles's Law to find the unknown final temperature.
481.97 °C
At a birthday pool party, the temperature is 28.50°C and the atmospheric pressure is 763.4 mmHg. One of the decoration helium balloons has a volume of 6.25 L. What would be the volume of the balloon if it were submerged in a swimming pool to a depth where the pressure is 922.3 mmHg and the temperature is 26.35°C?
5.11 L
Calculate the magnitude of q for a system that does 601000 kJ of work on its surroundings and for which the change in total internal energy is −1.00 × 10^4 kJ. Indicate whether heat is absorbed or released by the system.
5.91 × 10^5 kJ heat is absorbed
Consider the formation of nitrogen dioxide from nitric oxide and oxygen: 2 NO(g) + O2(g) → 2 NO2(g) If 7.37 L of NO is combined with excess O2 at STP, what is the volume in liters of the NO2 produced?
7.37 L
A gas-filled balloon with a volume of 2.55 L at 1.20 atm and 20°C is allowed to rise to the stratosphere (about 30 km above the surface of the Earth), where the temperature and pressure are −23°C and 3.00 × 10^−3 atm, respectively. Calculate the final volume of the balloon.
870.38 L
Given that 8.83 moles of carbon monoxide gas are present in a container of volume 27.10 L, what is the pressure of the gas (in atm) if the temperature is 89°C?
9.96 atm
Select which of the following standard enthalpy of formation values is not zero at 25°C: Na(s), CH4(g), H(g), Hg(l), Ne(g), S8(rhombic)
CH4 (g) H(g)
Select the elements and compounds from the following lists that are gases at room temperature. Elements: C,H,N,S,Ne,Kr,Al,F,Br Compounds: AlCl3, SiO2, NaI, CO2, LiBr, KCl, HCN, HCl, CaF2
Elements: H, N, Ne, Kr, F Compounds: CO2, HCN, HCl
Label each variable in the ideal gas law with the appropriate, commonly-used units. PV = nRT
P : atm V : L n : mol R : (L×atm)/(mol×K) T : K
Label each variable in the ideal gas law with the property it represents. PV = nRT
P : pressure V : volume n : number of mols R : universal gas constant T : absolute temperature
Determine the partial pressures and the total pressure in a 2.50-L vessel containing the following mixture of gases at 17.8°C: 0.0194 mol He, 0.0531 mol H2, and 0.149 mol Ne.
PHe = 0.184 atm PH2 = 0.507 atm PNe = 1.42 atm PTotal = 2.111 atm
A sample of ammonia (NH3) gas is completely decomposed to nitrogen and hydrogen gases over heated iron wool. If the total pressure is 887 mmHg after the reaction, calculate the partial pressures of N2 and H2. Enter your answers in scientific notation.
PN2 = 2.21729968 × 10^2 PH2 = 6.65189905 × 10^2
The density of water at 40°C is 0.992 g/mL. What is the volume of 1.41 g of water at this temperature
V= 1.42 mL
chemical properties
flammability, corrosiveness, reactivity with acids
Select the correct conversion factor for each step in the following roadmap for a substance with a density of 1 g/mL: mass (kg) -> mass (g) -> volume (mL)
mass (kg): x 1000 g/1 kg -> mass (g): x 1 mL/1 g -> volume (mL)
Physical properties
melting point, electrical conductivity, density, hardness, color
Assign each of the given labels to the flask that it correctly describes.
see pic
Categorize the pairs of variables given below as directly or inversely proportional for an ideal gas. For each pair, assume all other variables are held constant.
see pic
Indicate what information is required to convert between the parameters shown where A and B are two species in a chemical reaction.
see pic
Label the axes, phases and enthalpy changes shown in the diagram below.
see pic
Label the axes, phases, phase changes and important points on the phase diagram below.
see pic
Label the phase changes shown in the diagram below.
see pic
Match each chemical reaction with the correct diagram according to Hess' Law.
see pic
Predict the sign on the thermodynamic quantities listed below based on the scene representing a physical change in a piston-cylinder assembly.
see pic
Determine the final state and temperature of 100 g of water originally at 25.0°C after 50.0 kJ of heat have been added to it.
water and steam 100 °C
Given the following thermochemical equations, NO(g) + O3(g) → NO2(g) + O2(g) ΔH = −198.9 kJ/mol O3(g) → 3/2 O2(g) ΔH = −142.3 kJ/mol O2(g) → 2O(g) ΔH = +495 kJ/mol Determine the enthalpy change for the reaction 2NO2(g) → 2NO(g) + O2(g)
ΔH = +113.2 kJ/mol see pic
The molar heats of fusion and sublimation of lead are 4.77 and 182.8 kJ/mol, respectively. Estimate the molar heat of vaporization of molten lead.
ΔHvaporization = 178.03 kJ/mol
Consider the following two reactions: A → 2B, ΔH°rxn = H1 A → CΔ, H°rxn = H2 Determine the enthalpy change for the process 2B → C
ΔH°rxn = H2 − H1
Calculate the change in total internal energy for a system that releases 2.21 × 10^4 kJ of heat and does 6.03 × 10^4 kJ of work on the surroundings. Enter your answer in scientific notation. ΔU =___× 10___ kJ
ΔU = -8.24 × 10^4 kJ
Determine the mole fractions and partial pressures of CO2, CH4, and He in a sample of gas that contains 1.25 moles of CO2, 1.49 moles of CH4, and 3.31 moles of He, and in which the total pressure is 5.78 atm.
ΧCO2 = 0.207 PCO2 = 1.196 atm ΧCH4 = 0.246 PCH4 = 1.422 atm ΧHe = 0.547 PHe = 3.162 atm
