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Energetics and Thermodynamics

Entropy for reaction

Calculate "delta" S for the following reaction: H2(g) + Br2(l) --> 2HBr(g) given: S[H2(g)] = 0.131 kJ/K S[Br2(l)] = 0.152 kJ/K S[HBr(g)] = 0.199kJ/K a. 0.482 kJ/K b. 0.681 kJ/K c. 0.115 kJ/K d. -0.084 kJ/K e. 0.084 kJ/K

The relationship between delta S and G

Predict the signs of delta S and delta H for the melting of ice at 300K? a. Delta H > 0 and delta S > 0 b. Delta H > 0 and delta S < 0 c. Delta H < 0 and delta S > 0 d. Delta H < 0 and delta S < 0 e. Not enough information provided to answer question

Calculating delta S

Calculate "delta" S for the following reaction: H2(g) + Br2(l) --> 2HBr(g) Given: S[H2(g)] = 0.131 kJ/K S[Br2(l)] = 0.152 kJ/K S[HBr(g)] = 0.199kJ/K a. 0.482 kJ/K b. 0.681 kJ/K c. 0.115 kJ/K d. -0.084 kJ/K e. 0.084 kJ/K

Gibbs free energy

Which of the following are conditions for the standard Gibbs free energy? a. Ions or molecules in solution are present at one molar concentrations b. the temperature of the system is at 298K c. gases are present at one atmosphere partial pressure d. answers a and c are correct e. answers a, b, and c are corre

Entropy and Combustion of Hydrogen Gas

Which of the following is true for the combustion of hydrogen gas? a. "change in" H > 0 b. "change in" H < 0 c. "change in" S > 0 d. "change in" G > 0 at 300K e. "change in" G > 0 at all temperatures

Entropy, enthalpy and the freezing of water

Which of the following is true for the freezing of water at 298K? a. "change in" H < 0 b. "change in" H > 0 c. "change in" S = 0 d. "change in" S > 0 e. both answers a and d are correct

Entropy, Matter and Temperatures

Which of these statements is false? a. For a given material, a gas would have a greater entropy than the solid. b. For a given material, a liquid would have a greater entropy than the gas. c. At 0 K, an ordered pure crystalline solid has an entropy of zero. d. For a given material, the liquid has a greater entropy than the

Entropy

If "change in" G > 0, then a. K=0 b. K>0 c. K<0 d. K>1 e. K<1

Multiple choice question about entropy.

Which of the following has the least entropy? a. H20(s) b. H20(l) c. H20(g) d. Answers a and b have the same entropy e. Answers a, b, and c have the same entropy

Working with enthalpy of formation.

The reaction of 4.49 g of carbon and 9.21 g of oxygen, produced carbon dioxide, and 113.2 kJ of heat. What is the enthalpy of formation of carbon dioxide?

Specific heat - What is the mass of copper?

Copper has a specific heat of 0.382 J g-1 degrees Celsius -1. The temperature of an unknown mass of copper increases by 4.50 degrees Celsius when it absorbs 3.97 J of heat. What is the mass of copper?

Absolute entropy

Delta G sub f for Al203 = -1582 kJ/mol delta H sub f for Al203 = -1676 kJ/mol 1. Calculate absolue entropy for S for oxygen (g) if: S for Al(s) = 164 J/mol K S for Al2O3 (s) = 51.0 J/mol K 2. Calculate the heat required to raise the temperature of 35.0 g of aluminum from 800 degrees C to 2600 degrees C 3. To c

What to Include When Calculating Heat Emitted (q)

When calculating the amount of heat emitted (q): In which of these situations should you add the weight of what is added to the water, to the weight of the water itself? - 17g stick of boiled metal added to water in a calorimeter. or - 2g of NaOH added to water to measure the heat of dissolving.

Thermal Chemistry

I'm having problems understanding the ideas in the topic of thermal chemistry and would appreciate any sort of overview of the main concepts you could provide.