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DNA can be modeled as an elastic rod that can be twisted or bent. Suppose a DNA molecule of length L is bent such that it lies on the arc of a circle of radius
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Thermodynamics, Statistical Thermodynamics, & Kinetics
- The enthalpy of combustion of diamond is -395.4 kJ/mol. C s, dia O2 g CO2 g Determine the fH of C s, dia.arrow_forwardA 1.00 mol sample of H2 is carefully warmed from 22 K to 40 K at constant volume. a What is the expected heat capacity of the hydrogen? b What is q for the process?arrow_forwardA sample of methane of mass 45.0 g occupies a container at 310 K. Calculate the work done when the gas expands isothermally against a constant external pressure of 200 Torr until its volume increases by 12.11 L. 1 Torr = 133.33 Pa; MW of methane = 16.04 g/mol and R=8.3145 J/K mol. W= J. 4 sig. fig.arrow_forward
- I. Calculate total work done (in Joules) when 50 g of iron is dissolved in HCl in an open beaker at 45°C and 5 atm. (Molar mass of Fe = 56 g/mol; 1 L atm = 101.325 J) П. 2.0 moles of ammonia (NH3) were found to occupy a volume of 2 m3 at temperature 300 K. Calculate the pressure that would have been expected from Van der Waal's equation. For ammonia, a = 0.422 Nm*mol? and b = 0.0371 m³mol-1. R= 8.314 JK-'mol-1. (1 Jm³ = 1 Nm²) III. Draw a complete phase diagram for One-component system of H2O. Discuss how phase rule can be applied to the phase boundaries' and 'phase regions'. (OR) Derive an expression for the lowering of vapor pressure of a liquid when a non- volatile solute is dissolved in it.arrow_forwardMeasurements show that the energy of a mixture of gaseous reactants increases by 261. kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that – 175. kJ of work is done on the mixture during the reaction. Calculate the change in enthalpy of the gas mixture during the reaction. Round your answer to 3 kJ x10 significant digits. ? exothermic Is the reaction exothermic or endothermic? endothermicarrow_forwardThe French chemists, Pierre L. Dulong and Alexis T. Petit, noted in 1819 that the molar heat capacity of many solids at ordinary temperatures is proportional to the number of atoms per formula unit of the solid. They quantified their observations in what is known as Dulong and Petit's rule, which says that the molar heat capacity, Cp, of a solid can be expressed as Cp = N. 3R where N is the number of atoms per formula unit and R is the universal gas constant. The observed heat capacity per gram of a compound containing rubidium and oxygen is 0.64 J · K¯¹ · g¯¹. Use Dulong and Petit's rule to determine the empirical formula of the compound. empirical formula: Rb5O Incorrectarrow_forward
- The French chemists, Pierre L. Dulong and Alexis T. Petit, noted in 1819 that the molar heat capacity of many solids at ordinary temperatures is proportional to the number of atoms per formula unit of the solid. They quantified their observations in what is known as Dulong and Petit's rule, which says that the molar heat capacity, Cp, of a solid can be expressed as Cp = N. 3R where N is the number of atoms per formula unit and R is the universal gas constant. -1 The observed heat capacity per gram of a compound containing rubidium and oxygen is 0.64 J · K¯¹ . g¯¹. Use Dulong and Petit's rule to determine the empirical formula of the compound. empirical formula: Rb5O Incorrectarrow_forwardEthanol, C2H5OH, is brought to the boil at 1 atm. When an electric current of 0.682 A from a 12.0 V supply is passed for 500 s through a heating coil immersed in the boiling liquid, it is found that the temperature remains constant but 4.33 g of ethanol is vaporized. What is the enthalpy of vaporization of ethanol at its boiling point at 1 atm?arrow_forwardAn elastomer is a polymer that can stretch and contract. In a perfect elastomer the force opposing extension is proportional to the displacement x from the resting state of the elastomer, so |F| = kfx, where kf is a constant. But suppose that the restoring force weakens as the elastomer is stretched, and kf(x) = a − bx1/2. Evaluate the work done on extending the polymer from x = 0 to a final displacement x = l.arrow_forward
- A sample of 4.50 g of methane occupies 12.7 dm³ at 310 K. (a) Calculate the work done when the gas expands isothermally against a constant external pressure of 200 Torr until its volume has increased by 3.3 dm³. (b) Calculate the work that would be done if the same expansion occurred reversibly.arrow_forward1. A chemical reaction takes place in a container fitted with a piston of cross-sectional area 75.0 cm2 . As a result of the reaction, the piston is pushed out through 25.0 cm against an external pressure of 150 kPa. Calculate the work done by the system.arrow_forwardA piece of zinc of mass 5.0 g is placed in a beaker of dilute hydrochloric acid. It undergoesthe reaction Zn + 2 H+ Zn + H2. Assuming that the volume of the reactant is negligible compared to the volume of the gas and that the gas is perfect, calculate the work done by the system as a result of the reaction. The atmospheric pressure is 1.1 atm and the temperature 23 °C.arrow_forward
- Chemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage LearningGeneral Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage LearningPhysical ChemistryChemistryISBN:9781133958437Author:Ball, David W. (david Warren), BAER, TomasPublisher:Wadsworth Cengage Learning,
- Chemistry for Engineering StudentsChemistryISBN:9781337398909Author:Lawrence S. Brown, Tom HolmePublisher:Cengage LearningChemistry: Matter and ChangeChemistryISBN:9780078746376Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl WistromPublisher:Glencoe/McGraw-Hill School Pub Co