41 lines
1.6 KiB
Markdown
41 lines
1.6 KiB
Markdown
---
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title: Thermodynamics, Scattered
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date: 2024-11-10
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---
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# A Couple of Equations
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When it comes to energy transfer and phase changes there are only two useful equations.
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1. **Specific Heat Equation**: This equation is used to calculate the heat required to change the temperature of a substance without a phase change.
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$$
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\Delta \textbf{KE}=Q = mc\Delta T
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$$
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- $Q$ = heat energy added or removed (in joules, J)
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- $m$ = mass of the substance (in kilograms, kg)
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- $c$ = specific heat capacity of the substance (in J/kg°C)
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- $\Delta T$ = change in temperature (in °C or K)
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2. **Latent Heat (Potential Energy Buildup)**: This equation is used for phase changes, where energy changes the state of the substance (like melting or boiling) without changing its temperature.
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$$
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\Delta \textbf{PE} = Q = mL
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$$
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- \( Q \) = heat energy added or removed (in joules, J)
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- \( m \) = mass of the substance (in kilograms, kg)
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- \( L \) = latent heat of the substance (in J/kg), which could be the latent heat of fusion (for melting/freezing) or vaporization (for boiling/condensing)
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These equations together describe the heat energy required for changing the temperature of a substance and for changing its phase.
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**It is important to note the alternate arrangement of both:
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$$
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Q=nc_{\mathrm{mol}}\Delta T = \Delta \textbf{KE}
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$$
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or for the other Latent Heat equation:
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$$
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\Delta \textbf{PE} = Q = nL_{\mathrm{mol}}
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$$
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- $n$ is the number of moles
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- the subscript `mol` notates the same variable, but in units *per* mole.
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- ==You might see both==, at least they were both on the concept builders.
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