Heat and temperature space a carefully related topic, and as such, the difference in between the two can be a bit confusing. The core difference is the heat faces thermal energy, vice versa, temperature is more concerned v molecular kinetic energy.

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Whats the difference?

Heat describes the move of thermal energy in between molecules within a system and also is measured in Joules.<2> warm measures how power moves or flows. An item can acquire heat or lose heat, yet it cannot have heat. Warm is a measure up of change, never ever a home possessed by an object or system. Therefore, it is classified as a process variable.

Temperature defines the median kinetic energy of molecules in ~ a product or system and also is measure in Celsius (°C), Kelvin(K), Fahrenheit (°F), or Rankine (R). It is a measurable physical residential or commercial property of one object—also well-known as a state variable. Other measurable physics properties incorporate velocity, mass, and also density, to name a few.<3>


Heat is a deliver of thermal power caused through a distinction in temperature in between molecules.


Thermal power can be otherwise understood as the total microscopic kinetic and also potential energy of a system.

Second regulation of Thermodynamics

The second law the thermodynamics is a complicated topic the requires intensive study in the ar of thermodynamics to important understand. However, for the function of this article, only one small aspect requirements to it is in understood and also that is the truth that heat will constantly flow spontaneously native hotter building material to chillier ones. This simple statement defines why an ice cream cube doesn"t kind outside on a warm day or why it melts as soon as dropped in a key of warm water.

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Thought experiment

Imagine the previously mentioned ice cube dropped into a bowl of warm water—the ice cream must get heat (thermal energy) from the water in the key (see preceding paragraph). Adding thermal power leads to boost in the kinetic power of the ice molecule, and thus boost in temperature. This is known because temperature is in fact the measure of the median kinetic power of the molecules. Furthermore, the ice will proceed to acquire thermal power causing its molecules to relocate faster and eventually break their intermolecular binding or melt.

In conclusion, the move of warmth or thermal power will typically adjust the temperature the the substance, but not always! for example, at the minute when the ice cream in the bowl turns to water those water molecules will be in ~ the precise same temperature as as soon as they were ice. In this case, instead of the thermal power doing work-related to rise the kinetic energy, that does work to break the intermolecular bonds, bring about a adjust of state. However, as time goes on the temperature that the recently melted ice cream will boost until every little thing within the bowl reaches equilibrium—meaning a consistent temperature throughout.