One mole of a gas is placed in a closed system with a 20 l vessel initially at t = 300 k. the vessel is then isothermally expanded to 40 l. the gas follows the equation of state: p = rt/v + a/v2 where a = 240 l2 · atm/mol2 and r = 0.08206 l · atm/ mol · k. a. derive an expression relating (dh/dv)t to measurable properties. b. find dh for the gas in this process.

Given that

P = RT/V + a/V²

We know that

H= U + PV

For T= Constant  (ΔU=0)

ΔH= ΔU +Δ( PV)

ΔH= Δ( PV)

P = RT/V + a/V²

P V= RT + a/V

dH/dV = d(RT + a/V)/dV

dH/dV = - a/V²

So the expression of dH/dV

b)

In isothermal process

     (ΔU=0)

Now by putting the all values

ΔH = 17.06 L.atm

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.