A thermal physics question about steam and coffee, please could you help?

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SUMMARY

The discussion centers on calculating the mass of steam required to heat 0.18 kg of cold coffee from 14°C to 85°C using the formula E = mcΔθ. A total energy of 53,676 J is needed for this temperature increase. Participants confirm that the steam, initially at 100°C, must be condensed to release energy. The heat of vaporization of water at 100°C is crucial for determining the energy contribution from the steam.

PREREQUISITES
  • Understanding of the specific heat capacity (s.h.c.) of water
  • Familiarity with the formula E = mcΔθ for thermal energy calculations
  • Knowledge of the heat of vaporization of water at 100°C
  • Basic principles of thermodynamics related to phase changes
NEXT STEPS
  • Research the heat of vaporization of water at 100°C
  • Learn how to apply the formula E = ml for phase change calculations
  • Explore the concept of thermal equilibrium in heat transfer scenarios
  • Investigate practical applications of thermal physics in culinary settings
USEFUL FOR

Students studying thermal physics, educators teaching heat transfer concepts, and professionals in culinary science looking to understand the thermal dynamics of cooking processes.

slingboi
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Homework Statement


A coffee machine in a café passes steam at 100°C into 0.18kg of cold coffee (s.h.c. the same as that of water(4200j/kg/K)) to warm it. If the initial temperature of the coffee is 14°C, what mass of steam must be supplied to raise the temperature of the coffee to 85°C

Homework Equations


E = mcΔθ
possibly E = ml ?

The Attempt at a Solution


I have thought.
E = mcΔθ
= (0.18)(4200)(71)
= 53676J
so 53676J of energy is needed to increase the temperature of the cold coffee from 14°C to 85°C

OK so the steam is at 100°C so it is at 373.15K
how can I use the temperature of the steam to find out how much steam would be needed to increase the temperature of the cold coffee to 85°C?
Would the steam need to be condensed?
How could i go about finding out how much energy a unit of mass of steam would have?
 
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slingboi said:

Homework Statement


A coffee machine in a café passes steam at 100°C into 0.18kg of cold coffee (s.h.c. the same as that of water(4200j/kg/K)) to warm it. If the initial temperature of the coffee is 14°C, what mass of steam must be supplied to raise the temperature of the coffee to 85°C


Homework Equations


E = mcΔθ
possibly E = ml ?


The Attempt at a Solution


I have thought.
E = mcΔθ
= (0.18)(4200)(71)
= 53676J
so 53676J of energy is needed to increase the temperature of the cold coffee from 14°C to 85°C

OK so the steam is at 100°C so it is at 373.15K
how can I use the temperature of the steam to find out how much steam would be needed to increase the temperature of the cold coffee to 85°C?
Would the steam need to be condensed?
How could i go about finding out how much energy a unit of mass of steam would have?

Yes, you need to condense the steam. Look up the heat of vaporization of water at its normal boiling point 100C.
 

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