Concept:The First Law of Thermodynamics is the law of conservation of energy applied to chemical systems. It states that energy cannot be created or destroyed, only transferred as heat or work.
Formula:$$ \Delta E = q + w $$
Solution:- The mathematical statement of the 1st law dictates that the total change in a system's internal energy (\( \Delta E \) or \( \Delta U \)) is equal to the heat added to the system (\( q \)) plus the work done on the system (\( w \)).
- Therefore, \( \Delta E = q + w \) is the universally recognized correct equation.
Why other options are incorrect:Option B is Boyle's Law for gases. Option C is the de Broglie wavelength equation from quantum mechanics. Option D is Einstein's mass-energy equivalence equation.
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