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dear2009

New member
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Oct 8, 2009
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33
Dear Math Help Participants,


The ideal gas law states that

PV = nRT,

where P is pressure (in atmospheres), V is volume (in liters), n is the number of moles of gas atoms (a mole contains 6.02 x 1023 atoms), R is the gas constant (0.08206 L atm mol­–1 ­K­–1). Suppose 5 moles of helium is contained in a cylinder whose volume is decreasing at the rate of 2 L/sec, while the pressure is increasing at the rate of ½ atmosphere per second. How fast is the temperature changing when the pressure is 4 atm, the volume is 100 liters, and the temperature is 300K? HINT: n is constant here, unlike the examples! (answers given are approximate, in units of degrees Kelvin per second)


Any help would be greatly appreciated. Thanks in advance
 
Rewrite everything that moves as a function of time 't': P(t)*V(t) = n*R*T(t)

Implicit Derivative wrt 't': P(t)*(dV/dt) + V(t)*(dP/dt) = n*r*(dT/dt)

Now what?
 
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