Is Heat Absorption Always Linked to Temperature Increase?

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SUMMARY

The discussion centers on the relationship between heat absorption and temperature changes, specifically addressing the nuances of thermodynamic principles. It establishes that while an increase in temperature generally indicates heat absorption, this is not a universal rule. The first law of thermodynamics is highlighted, particularly the equation ΔU=Q+W, which illustrates that internal energy can increase without heat transfer in adiabatic processes. Additionally, it is noted that during phase changes, such as boiling, heat can be absorbed without a corresponding increase in temperature.

PREREQUISITES
  • Understanding of the first law of thermodynamics
  • Familiarity with concepts of internal energy (U), heat transfer (Q), and work (W)
  • Knowledge of phase changes, particularly boiling and evaporation
  • Basic principles of adiabatic processes
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  • Study the first law of thermodynamics in detail
  • Explore adiabatic processes and their implications in thermodynamics
  • Investigate phase transitions and their effects on temperature and heat absorption
  • Learn about the specific heat capacity of substances during phase changes
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Students of thermodynamics, physicists, engineers, and anyone interested in the principles of heat transfer and energy conservation.

Miike012
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I have a question about energy.

If temperature is raising does this mean that heat is being absorbed or evolved?

and if heat is being absorbed this means that temp is raising?
and temp is lowering if heat is being evolved?
 
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If something is increasing in temperature then it is generally absorbing heat. However, things can increase in temperature without heat transfer too. Consider the first law of thermodynamics:

\Delta U=Q+W

where U is the internal energy. If a process is adiabatic (i.e. no heat transfer allowed, Q=0), then the internal energy can still be increased if work is done on the system (W>0), for example by compressing a gas in an insulated container.

If heat is being absorbed then it does not necessarily imply that the temperature is increasing. Consider any pure liquid at its boiling point and at constant pressure -- as more heat energy is transferred to the system, the temperature will remain constant until all the liquid has evaporated.
 

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