28.5 expands p2.6 a 1.50 mole sample of an ideal gas at ℃ isothermally from an initial volume of 22.5 dm3 to a final vol ume of 75.5 dm3. calculate w for this process (a) for expan sion against a constant external pressure of 1.00 × 105 pa, and (b) for a reversible expansion. p2.7 calculate q, w, δ1, and δ h if 2.25 mol of an ideal gas with cv, m 3r/2 undergoes a reversible adiabatic expansio ume v, 25.0 m3. the initial temperature is 275 k. on from an initial volume vi = 5.50 m3 to a final vol p2.8 calculate w for the adiabatic expansion of 2.50 mol of a ideal gas at an initial pressure of 2.25 bar from an initial temper ature of 450. k to a final temperature of 300. k. write an expression for the work done in the isothermal reversible expan sion of the gas at 300. k from an initial pressure of 2.25 bar. what value of the final pressure would give the same value of w as the first part of this problem? assume that cpm 5r/2. 0.9970 g cm-3, and cpm 75.3 j k1 mol 1.the change in volume with temperature is given by av-vinitia1βδ t where β, the coefficient of thermal expansion, is 2.07 × 10-4 k-1 . if the temperature of 325 g of water is increased by 25.5 k, calculate w, q, ah, and δu. p2.10 a muscle fiber contracts by 3.5 cm and in doing so lifts a weight. calculate the work performed by the fiber assume the muscle fiber obeys hooke's law f-kx with a force constant k of 750. n m-1 p2.11 a cylindrical vessel with rigid adiabatic walls .

  sequence  is a continuous and distinctive band of  stars  that appears on plots of stellar  color  versus  brightness. these color-magnitude plots are known as  hertzsprung–russell diagramsafter their co-developers,  ejnar hertzsprungand  henry norris russell. stars on this band are known as  main-sequence stars  or  dwarf stars. these are the most numerous true stars in the universe, and include the earth's  sun.after condensation and ignition of a star, it generates  thermal energy  in its dense core region through  nuclear fusion  of  hydrogen  into  helium. during this stage of the star's lifetime, it is located on the main sequence at a position determined primarily by its mass, but also based upon its chemical composition and age. the cores of main-sequence stars are in  hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of  gravitational collapse  from the overlying layers. the strong dependence of the rate of energy generation on temperature and pressure to sustain this balance. energy generated at the core makes its way to the surface and is radiated away at the  photosphere. the energy is carried by either  radiation  or  convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.the main sequence is sometimes divided into upper and lower parts, based on the dominant process that a star uses to generate energy. stars below about 1.5 times the  mass of the sun  (1.5  m☉) primarily fuse hydrogen atoms together in a series of stages to form helium, a sequence called the  proton–proton chain. above this mass, in the upper main sequence, the nuclear fusion process mainly uses atoms of  carbon,  nitrogen  and  oxygen  as intermediaries in the  cno cycle  that produces helium from hydrogen atoms. main-sequence stars with more than two solar masses undergo convection in their core regions, which acts to stir up the newly created helium and maintain the proportion of fuel needed for fusion to occur. below this mass, stars have cores that are entirely radiative with convective zones near the surface. with decreasing stellar mass, the proportion of the star forming a convective envelope steadily increases. main-sequence stars below 0.4  m☉undergo convection throughout their mass. when core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.in general, the more massive a star is, the shorter its lifespan on the main sequence. after the hydrogen fuel at the core has been consumed, the star  evolves  away from the main sequence on the hr diagram, into a  supergiant,  red giant, or directly to a  white dwarf.

The answer is trial 3.

Don't smoke.it ruins your life.confront your husband on how you are feeling and why you're depressed.weed is never the answer.there are so many more options out there for depression.weed will make the depression worse.so, stay clean and you will have support