What volume and mass of steam at 100 celsius and 760. torr (or 1 atm) would release the same amount of energy as heat during condensation as 65.5cm^3 of liquid water would release during freezing?

Explanation:

The given data is as follows.

          Volume = 65.5

          Temperature =

          Pressure = 760 torr or 1 atm

As we know that q =  

where,    m = mass

            = latent heat of fusion

As density of water is 1.0 g/ml. Hence, mass of water in liquid state is calculated as follows.

                   mass = density × volume

                            =            (as 1 ml = 1 )

                           = 65.5 g

As heat of fusion of ice is 333.55 J/g. Hence, calculate the heat energy as follows.

                    q =  

                       =

                       = 21847.52 J

And, heat of vaporization of water is 2257 J/g.

Also,                q =

where,       = heat of vaporization

Therefore, we will calculate the mass of steam as follows.

                        q =

                     21847.52 J =            

                       m = 9.68 g

It is known that density of steam water is 0.0006 g/ml. Hence, calculate the volume of steam as follows.

                Volume =

                              =

                              = 16133.33 ml

or,                           = 16.13 L             (as 1 L = 1000 ml)

Thus, we can conclude that 9.68 g of steam condenses will release the same amount of energy as 65.5 g of freezing liquid water and its volume is 16.13 L.

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.