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  1. Temperature. 2 a) increase as go from one mole of solid to two moles of aqueous ions (one mole of Na+(aq) and one mole of Cl-(aq)) b) decrease as go from one mole of liquid to one mole of solid. c) increase as go from two moles of gas to three moles of gas. d) decrease as go from four moles of gas to two moles of gas.

  2. 2 The zeroth law of Thermodynamics. . . 11 2.1 Thermodynamical systems 2.2 Thermodynamical (macro) versus micro states 2.3 Thermodynamical equilibrium 2.4 Equation of state 2.5 The zeroth law 3 The first law of Thermodynamics. . . . . . 17 3.1 Thermodynamical change 3.2 The first law 3.3 Internal energy 3.4 Functions of state vs functions of path

    • What is true of Isothermal Process. (a) ΔT >0. (b) ΔU=0. (c) ΔQ=ΔW. (d) PV=constants. Solution. In an Isothermal Process. Temperature remains constant ΔT =0.
    • Two absolute scales A and B have triple points of water defined as 200A and 350A. what is the relation between Tand T. Solution-2. Given that on absolute scale.
    • A gas is contained in a cylinder with a moveable piston on which a heavy block is placed. Suppose the region outside the chamber is evacuated and the total mass of the block and the movable piston is 102 kg.
    • At 27°C,two moles of an ideal monatomic gas occupy a volume V.The gas is adiabatically expanded to a volume 2V. (a)Calculate the ratio of final pressure to the initial pressure.
  3. into doing work. This statement of energy conservation is the first law of thermodynamics, which is defined more formally below. Related End-of-Chapter Exercises: 1 and 13. The first law of thermodynamics is a statement of energy conservation as it relates to a thermodynamic system. Heat, which is energy transferred into or out of a system, can be

    • Last time: The First Law of Thermodynamics
    • = Q - W
    • C ~ α Substances with more internal
    • ACT 1
    • ACT 1: Solution
    • Work Done by a Gas
    • V V V
    • Constant-Pressure Heat Capacity of an Ideal Gas
    • U = -W by.
    • Four Thermodynamic Processes of Particular Interest to Us
    • f dV
    • Example: Escape Velocity
    • Next Week

    Energy is conserved !!! change in total internal energy heat added to system work done on the system alternatively:

    by Note: For the rest of the course, unless explicitly stated, we will ignore KE CM, and only consider internal energy that does not contribute to the motion of the system as a whole.

    V degrees of freedom require more energy to produce the same temperature increase: Why? Because some of the energy has to go into “heating up” those other degrees of freedom! The energy is “partitioned equally” “equipartition”

    Consider the two systems shown to the right. In Case I, the gas is heated at constant volume; in Case II, the gas is heated at constant pressure. Compare Q , the amount of heat needed to

    Consider the two systems shown to the right. In Case I, the gas is heated at constant volume; in Case II, the gas is heated at constant pressure. Compare Q , the amount of heat needed to

    When a Consider a cylinder filled with gas. For a small displacement gas expands, it does work on its environment. A dx, the work done by the gas is dW by = F dx = pA dx = p (Adx)= p dV

    The amount of work performed while going from one state to another is not unique! It depends on the path taken, i.e., at what stages heat is added or removed. That’s why W is called a process variable. because T varies differently along the paths. (Heat is added at different times.)

    Add heat to an ideal gas at constant pressure, allowing it to expand. We saw in the Act that more heat is required than in the constant volume case, because some of the energy goes into work: work W by

    α Nk U = − T = − W by p = V − NkT V V T α = − V dT dV → α ∫ = − ∫ T V α ln ( T ) = − ln ( V ) + constant ln ( T α ) + ln ( V ) = ln ( T α V ) = constant V α T = constant Using pV = NkT, we can also write this in the form: pV γ = constant Note that pV is not constant. The temperature is changing.

    Isochoric (constant volume) Isobaric (constant pressure)

    Isothermal process - ideal gas. FLT Definition of work then use ideal gas law Integral of dV/V Note that the heat added is negative - heat actually must be removed from the system during the compression to keep the temperature constant.

    How much kinetic energy must a nitrogen molecule have in order to escape from the Earth’s gravity, starting at the surface? Ignore collisions with other air molecules. How about a helium atom? At what temperatures will the average molecule of each kind have enough energy to escape?

    Heat capacity of solids & liquids Thermal conductivity Irreversibility

  4. Answer is (C). 7. Steam enters a turbine with a velocity of 40 m/s and an enthalpy of 3433.8 kJ/kg. At the outlet, 2 meters lower than the inlet, the velocity is 162 m/s, and the enthalpy is 2675.5 kJ/kg. A heat loss of 1 kJ/kg is experienced from the turbine casing. The work output per unit mass is closest to. 650 kJ/kg.

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  6. Report. This document contains 40 multiple choice questions about thermodynamics. It covers topics like the latent heat of steam, gas laws, Carnot and Otto cycles, phase changes of water, units used in thermodynamics, and the laws of thermodynamics. Each question is followed by an answer and an option to add comments.

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