Delta U?
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Re: Delta U?
Delta U is the change in internal energy due to the transfer of energy as work and/or heat. Delta U = q + w
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Re: Delta U?
Just like the previous replies state, ΔU is the change in internal energy of the system. To add on to what the previous replies said, you can think of U as the kinetic energy + potential energy of the particles that your sample is comprised of.
Internal energy is a state function, like enthalpy. It is also dependent on temperature (also a state function); this is due to the proportional relationship between temperatures of gases and average kinetic energy of particles (this KE contributes to U, or the internal energy).
Internal energy is a state function, like enthalpy. It is also dependent on temperature (also a state function); this is due to the proportional relationship between temperatures of gases and average kinetic energy of particles (this KE contributes to U, or the internal energy).
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Re: Delta U?
I believe the delta symbol always means change in the given variable which in this case is U(final)-U(initial)=(delta) U. U is the energy of the system.
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Re: Delta U?
Delta U is referred to as the change in internal energy of a system. Delta U is actually equal to q + w whereas q is the heat input or Delta H. w= -P(Vfinal-Vinitial). If in a problem the system has a constant volume and no expansionary work is performed then w=0.
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Re: Delta U?
Adding onto the previous posts, if delta u is positive, then u(final) > u(initial). If delta u is negative, then u(final) < u(initial).
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Re: Delta U?
U is the internal energy of the system. Because the internal energy of a molecule would consist on the summation on the energies within atoms, bonds, etc (too complex to calculate), we use Delta U to discuss the change in the internal energy of a system without having to know the actual numerical value of the internal energy
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