Water, initially saturated vapor at 4 bar, fills a closed, rigid container. the water is heated until its temperature is 400°c. for the water, determine the heat transfer, in kj per kg of water. kinetic and potential energy effects can be ignored.

q=471.19kj.kg

Explanation:water constant volume = C

First state

Quantity X1=1

Pressure=1 bar

Second state

T2=400C

Required heat transferred q in kj.kg

Assumption:

System is at equilibrium

Kinetic and Potential energy are neglected

Therefore, from 1st law of thermodynamics q - w=∆u. . . . 1

From steam table A

U1=Ug=2553.6kj.kg

U2=Vg=1625m³.kg

V1=V2=4625m³.kg

From steam Table B

Px= 7 bar

Vx=4667kj.kg

Ux=3026.6kj.kg

Py= 10 bar

Vy= 3066kj.kg

Uy=2957.5kj.kg

Assuming a Linear interpolation

Ux-V2/Ux-Vy=Vx-U2/Ux-Vy

U2 =Vx-{vx-vy}× vx-v2/Ux-Vy

U2 = 3026.6 - (3026.6-2957.3)× 4667-4625/4667-3066

=3024.79kj.kg

Therefore, from q-w=∆u

q=3024.79-253.6

=471.19kj.kg

Where u = internal energy

V= specific volume

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods