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Energetics and Thermodynamics

Thermodynamics : Heats of Formation

For the reaction CH4 (g) + N2 (g) + 164 kJ 6 HCN(g) + NH3 (g) at 25degrees C and 1 atm of pressure ÄGo = 159 kJ. Calculate ÄSo at 25degrees C. ÄHfo for CH4 (g) = -74.77 kJ/mol and ÄHfo for NH3 (g) = -46.09 kJ/mol. What is ÄHfo for HCN(g) ?

Boiling Point of Ethanol from Gibbs Free Energy

Delta S (standard conditions) for the following reaction is favorable even though delta H (standard conditions) is not: C2H5OH (l) <-> C2H5OH (g) Assume that ethanol boils at the temperature where delta G (standard conditions) for this reaction becomes zero. Use the values of delta H and delta S for this reaction to estimate

Heat of Combustion Problems

1) Calculate the heat of combustion for C2H6 from the following information: C2H4+3O2-> 2CO2+2H2O C2H4+H2->C2H6 H2+1/2O2->H2O 2) Discuss the idea that the standard of living in society might be measured in units of kJ/person available in that society. The unit itself is called energy in chemical reactions if that helps

Thermodynamics : Spontaneity of Reactions and Gibbs Free

Urea (NH2CONH2), an important nitrogen fertilizer, is produced industrially by the reaction 2 NH3(g) + CO2(g) &#8594; NH2CONH2(aq) + H2O(l) Given that delta G^o = -13.6 kJ, calculate delta G at 25 oC for the following sets of conditions. (a) 10 atm NH3, 10 atm CO2, 1.0 M NH2CONH2 (b) 0.1 atm NH3, 0.1 atm CO2, 1.0 M NH2CON

Lab Report : The Enthalpy Change of a Chemical Reaction

The Enthalpy Change of a Chemical Reaction Procedure #1: 1. Take a calorimeter from the Glassware shelf and place it on the workbench. 2. Take a balance from the Tools shelf and drop it on the calorimeter. Record the mass of the empty calorimeter. 3. Take a thermometer from the Tools shelf and drop it onto the calo

Contract or Expanding Gases

1. A sample of N2 gas occupies 2.40 L at 20oC. If the gas is in a container that can contract or expand at constant pressure, at what temperature will the N2 occupy 4.80 L? 10oC 40oC 146oC 313oC 685oC 2. When 0.56 g of Na(s) reacts with excess F2(g) to form NaF(s), 13.8 kJ of heat is evolved at standard-state cond

Physical chemistry

I just need the calculation part done. The mass of the solutes is as follows: .502g Tris and .4999g KNO3 and .4995g Pb(NO3)2 Solution Calorimetry: Heat of Ionic Reaction Solution Calorimetry is a convenient way of experimentally determining the heat of reaction in a liquid medium. Measurements in this lab will be made

Enthalpy, Heat of Formation and Heat of Vaporization

1. Consider this data for compound X: &#916;Hf 505.4 J/g &#916;Hvap= 3489J/g Specific heat: X (s) = 0.96 J/g °C, X (1) = 3.88 J/g °C, X (g) = 1.21 J/g °C Normal boiling point: 46.8 °C Normal freezing point: - 29.8 °C a. Calculate the total energy change if 10.0 grams of X is changed from 11.0 °C to 88.9 °C. b. Write

Predicting Changes in a Thermodynamic System

A) The pressure of a monoatomic ideal gas in a closed system is reversibly and isochorically (constant volume) increased. Determine whether each of the following quantities is less than, equal to, or greater than zero. ΔT ΔV w q ΔP ΔU ΔH ΔS b) A real gas is found to have a molar volume that is 90% of the

Derive and Apply Heat Capacity

Suppose that the enthalpy of some substance over a large temperature range can be expressed as a function of the temperature (where alpha, beta and gamma are constants): H =alpha*ln(T) + ln(gamma) + beta/T^2 a) What is the heat capacity of this substance at constant pressure? b) You begin with two samples each contai

To determine effect of entropy

A process run infinitesimally slowly at equilibrium and reversed to its original state Motion of a frictionless pendulum Evaporation of water from a cup Solid and liquid water combined together at STP Ice melting to water above the melting point Isothermal expansion of a real gas Please see the attache

Gibbs Free Energy and Spontaneity of Reactions

I completed part A and the second part asks: What can be said about the spontaneity of this reaction? C diamond to C graphite The reaction (as written) is spontaneous. The reverse reaction is spontaneous. the system is in equilibrium at 298 K.

Thermodynamics : Predicting Spontaneity of Reactions

From the values given for delta H* and delta S*, calculate delta G* for each of the following reactions at 298 K. If the reaction is not spontaneous under standard conditions at 298 K, at what temperature (if any) would the reaction become spontaneous? a) 2 PbS (s) + 3 O2 (g) ---> 2 PbO (s) + 2 SO2 (gO

General Chemistry - Heat of Reaction and Caloric Intake

A body generates 5900kJ of energy/h during heavy exercise. How many grams of C6H12O6 is needed for 22 minutes of exercise? C6H12O6 burns at 4.00 kcal/g. Find the mass of potato chipes needed to eat to not lose weight. Full solution please thank you

Reaction Enthalpies from Heats of Formation

Calculate the enthalpy for the combustion of pentane. Please see the attached file for the fully formatted problems. Part B The combustion of pentane, , occurs via the reaction with heat of formation values given by the following table: Substance ( ) 35.1 393.5 241.8 Calculate the enthalpy for th

Coffee (Styrofoam) Cup Calorimetry

2 moles of a compound are allowed to react in a foam coffee cup that contains 160 grams of water. The reaction caused the temperature of the water to rise from 21 to 24.7 degrees Celsius. What is the enthalpy of this reaction? Assume that no heat is lost to the surrounding or to the coffee cup itself. Please answer in kilojou

Gases, Temperature and Pressure

A 1.00-L bulb of methane at a pressure of 10.0 kPa is connected to a 3.00-L bulb of hydrogen at 20.0 kPa; both bulbs are at the same temperature. (a) After the gases mix, what is the total pressure? (b) What is the mole fraction of each component in the mixture? Every time I start to answer this question I always end up wit

A Problem that Deals with Ideal Gases

For a certain ideal gas, Cv = 2.5R for all temperatures. Calculate q, w, &#916;U and &#916;H when 2.00 mol of this gas undergoes each of the following processes: (a) a reversible expansion at a constant pressure of 1 bar from a volume of 20.0 dm3 to 40.0 dm3. (b) a reversible isothermal compression from (0.50 bar, 40.0 dm3)

Thermodynamics : Enthalpy of Formation, Heats of Reaction and Heating Curves

1.) Use the values of &#8710;Hof given below to calculate (in kJ) &#8710;Horxn for the following reaction: C2H5OH (l)+ 3O2(g) &#8594; 2CO2(g) + 3H2O(g) Given: &#8710;Hof (kJ/mol) C2H5OH (l) -278 O2(g) 0 CO2(g) -394 H2O(g) -242 2.) The graph below shows the heating curve of water. Use this graph to answer the fol

Thermodynamics, Work and Volume

In a combustion cylinder, the total internal energy change (delta E) from the burning of a fuel is -174 kJ. The cooling system that surrounds the cylinder absorbs 47 kJ as heat. a.) How much work can be done by the fuel in the cylinder? b.) Assuming an initial volume of 100.0 L and an external pressure of 1.00 atm, what is the

Calorimetry, Heat Capacity, Temperature Change and Changes of State

Please see the attached file for the fully formatted problem(s). Heat, Energy, and Changes of State Part A How much energy in joules would be absorbed by 3.0 L of liquid oxygen as it vaporized? The density of liquid oxygen at its boiling point is 1.14 kg/L , and its heat of vaporization is 213 kJ/kL . Express yo

Equilibrium constant

Please see the attached file for full problem descriptions: 1. A quantity of 0.20 mol of carbon dioxide was heated to a certain temperature with an excess of graphite in a closed container until the following equilibrium was reached: C (s) + CO2 (g) <--> 2CO (g) Under these conditions, the average molar mass of the gas was

Gibb's Free Energy Change and Equilibrium Constant

Please see the attached file and show work. The following reaction, which takes place just before the citric acid cycle, is catalyzed by the enzyme lactate dehydrogenase CH3COCOO- + NADH + H+ <----> CH3CH(OH)COO- + NAD+ From the data listed in Table 7.2, calculate the value of Gibb's free energy change deltaG and the equ

Specific heat to convert ice to steam

How much heat (energy) is required to convert 52.0 g of ice at -10.0 degree C to steam at 100 degree C? specific heat of ice: 2.09 J/g degree Celsius Delta H fus specific heat of water: 4.18 J/g Celsius Delta H vap= 40.7 kJ/mol specific heat of steam: 1.84 J/g Celsius

Heat needed to convert ice to liquid water

Calculate the amount of heat that must be absorbed by 10.0 g of ice at -20.0 degrees C to convert it to liquid water at 60.0 degree C. Specific heat (ice) = 2.1 j/g degree C Specific heat (water) delta H (fus)= 6.0 kJ/mol

the change in enthalpy and entropy

5. C(s) + CO2(g) ---> 2 CO(g) Carbon (graphite), carbon dioxide and carbon monoxide form an equilibrium mixture as represented by the equation above. (a) Predict the sign for the change in entropy, deltaS, for the reaction. Justify your prediction. (b) In the table below are data that show the percent of CO in the equi

Combustion of Pentane, Enthalpy, and Graham's Law of Diffusion

3. Consider the hydrocarbon pentane, C5H12 (molar mass 72.15 g). (a) Write the balanced equation for the combustion of pentane to yield carbon dioxide and water. (b) What volume of dry carbon dioxide, measured at 25 C and 785 mm Hg, will result from the complete combustion of 2.50 g of pentane? (c) The complete combusti

Urea - Heat of Dissolution Laboratory

Hello! I have two different experiments attached, please put them in Standard Deviation. For example: Experiment 1: Keq=____,(delta)H=___J, (delta)G = _____, (delta)S =____J/K Experiment 2: Experiment 3: Standard Deviation for Keq: mean=_____ St.Dev2=(___) + (___) + (___) all over 2 =__ + __+ __ St. Dev=___ St.Dev of