Determine the final temperature of the mixture

In summary, a student is trying to determine the final temperature of a mixture of 21.4 grams of ice and 13.1 grams of steam in a sealed and insulated container. Using the equations Q=mcΔT and Q=mL, the student attempted to solve for the final temperature but encountered a discrepancy. The reason for this is that the energy required to melt the ice is less than the energy required to condense the steam, resulting in a balance/remainder of energy that is used to heat the liquid water. Taking this into account, the final equilibrium temperature can be determined using the equation Q=mcΔT from the starting point of two amounts of liquid water at different temperatures. It is important to note that
  • #1
Stomper123
6
0

Homework Statement


A student places 21.4 grams of ice at 0.0C and 13.1 grams of steam at 100.0C in a sealed and insulated container. Determine the final temperature of the mixture.
m(ice)= 21.4 g or 0.0214 kg
m(steam)= 13.1 g or 0.0131 kg
Ti(ice)= 278.15 K
Ti(steam)= 378.15 K
Tf(ice)=Tf(steam)
Latent heat of fusion: 334 kJ/Kg
Latent heat of vaporization 2257 kJ/kg

Homework Equations


Q=mcΔT
Q=mL
Qt(hot)= -Qt(cold)

The Attempt at a Solution


I did it on paper and attempted to solve for T2 using latent heat of fusion on one side and the vaporisation on the other side but ended up getting 57.74K which I know is impossible. I think one of the objects doesn't fully change state but I don't know how to do those kinds of problems.
 
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  • #2
I think what you can do is look at the difference between the energy required to melt that amount of ice, and the energy required to condense that amount of steam. The former is less than the latter. Once enough energy has been transferred to melt all of the ice, the steam is still condensing, and the balance/remainder is used to heat that 0.0 C liquid water. Once the condensing is finished, you'll have some newly condensed water at just under 100 C, and some other liquid water at some temperature that depends on how much heating took place after melting (which depends on this difference/balance/remainder of energy I referred to in bold above). Now you can just use Q = mc delta T to find the final equilibrium temperature from this starting point of two amounts of liquid water at two different temperatures.
 
  • #3
Check your absolute temperature values. I think you will find them to be slightly off.
 

FAQ: Determine the final temperature of the mixture

What factors influence the final temperature of a mixture?

The final temperature of a mixture is influenced by several factors, including the initial temperatures of the substances being mixed, the specific heat capacities of the substances, the mass of each substance, and any external heat sources or sinks.

How can I calculate the final temperature of a mixture?

The final temperature of a mixture can be calculated using the law of conservation of energy. This involves setting the sum of the initial energies equal to the sum of the final energies and solving for the final temperature using the specific heat capacities and masses of the substances.

Is it possible for the final temperature of a mixture to be lower than the initial temperatures?

Yes, it is possible for the final temperature of a mixture to be lower than the initial temperatures. This can occur if one of the substances has a higher specific heat capacity or a larger mass, or if there is an external heat sink present.

Can the final temperature of a mixture be higher than the initial temperatures?

Yes, the final temperature of a mixture can be higher than the initial temperatures if one of the substances has a lower specific heat capacity or a smaller mass, or if there is an external heat source present.

How does the mixing process affect the final temperature of a mixture?

The mixing process itself does not significantly affect the final temperature of a mixture. The final temperature is primarily determined by the properties and initial temperatures of the substances being mixed.

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