36.0k views
5 votes
A 1.00 kg block of aluminum is heated at atmospheric pressure so that its temperature increases from 22.0°C to 40.0°C.

(a) Find the work done on the aluminum._________ mJ(b) Find the energy added to it by heat.__________ kJ(c) Find the change in its internal energy.___________ kJ

User Guyaloni
by
7.8k points

1 Answer

3 votes

Answer:

(a). The work done on the aluminum is -48.6 mJ.

(b). The energy added to it by heat is 16.58 kJ.

(c). The change in its internal energy is 1.658 kJ.

Step-by-step explanation:

Given that,

Mass of block = 1.00 kg

Initial pressure =22.0°C

Final pressure = 40.0°C

(a). We need to calculate the work done on the aluminum

Using formula of work done


W=-P\Delta V


W=-P((3\alpha m(T_(f)-T_(i)))/(\rho))

Here,
\Delta V=(3\alpha m(T_(f)-T_(i)))/(\rho)

Put the value into the formula


W=-1.01325*10^(5)*((3*24*10^(-6)*1.00(40-22))/(2700))


W=-48.6*10^(-3)\ J


W=-48.6\ mJ

(b). We need to calculate the energy added to it by heat

Using formula of heat


Q=mc\Delta T

Put the value into the formula


Q=1.0*921*(40-22)


Q=16.58\ kJ

(c). We need to calculate the change in its internal energy

Using formula of internal energy


Q=\Delta U+W


\Delta U=Q-W

Put the value into the formula


\Delta U=1658+0.0486


\Delta U=1658.04\ J


\Delta U=1.658\ kJ

Hence, (a). The work done on the aluminum is -48.6 mJ.

(b). The energy added to it by heat is 16.58 kJ.

(c). The change in its internal energy is 1.658 kJ.

User Sebastian Redl
by
7.8k points