Question

A reaction taking place in a container with a piston-cylinder assembly absorbs 4850. J of heat and has a change in the internal energy of 1618.5 j. What is the final volume of the container if the reaction occurs under a constant external pressure of 5.5 atm and the initial volume of the container is 10.5 l?

Answer 1

Answer:

$V_f = 16.3 Ltr$

Explanation:

As per first law of thermodynamics we know that

heat absorbed = change in internal energy + Work done

so we have

$Heat = 4850 J$

$\Delta U = 1618.5 J$

so work done is given as

$4850 = 1618.5 + W$

$W = 3231.5 J$

now we know that at constant pressure the work done is given as

$W = P\Delta V$

$3231.5 = P(V_f - V_i)$

$3231.5 = 5.5 \times 1.01 \times 10^5(V_f - 10.5 \times 10^{-3})$

$V_f = 16.3 \times 10^{-3} m^3$

or we have

$V_f = 16.3 Ltr$