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Find the isobaric expansion coefficient dV/dT and the isothermal pressure-volume coefficient dV/dP of a solid that has the equation of state V+bpT–cT²=0.

(a) b/c,1/b
(b) 1/b, b/c
(c) c/b, 1/b
d 1/c, c/b

User DenStudent
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Final answer:

The equation of state V + bpT - cT² = 0 is differentiated to find the isobaric expansion coefficient dV/dT and the isothermal pressure-volume coefficient dV/dP, resulting in bp - 2cT and bT, respectively, although the expression for dV/dT contains the variable T, which prevents it from being stated purely in terms of constants b and c.

Step-by-step explanation:

The student has presented the equation of state for a solid as V + bpT - cT² = 0, where V is the volume, p is the pressure, T is the temperature, and b and c are constants.

To find the isobaric expansion coefficient dV/dT and the isothermal pressure-volume coefficient dV/dP, we take partial derivatives of the equation with respect to T and P, respectively.

For the isobaric expansion coefficient dV/dT (at constant pressure), we differentiate V with respect to T, treating p as a constant:

dV/dT = bp - 2cT

Since we're looking for a coefficient, we want the expression in terms of 'pure' coefficient not depending on other variables such as T. For the given equation, as T approaches zero (hypothetically), the term -2cT would vanish, leaving us with bp as a proportional constant.

However, the question is about the general form, not a limit case. Thus, based on the information given, we do not have enough to provide a complete answer strictly in terms of constants b and c. To truly resolve this, additional information or constraints on the system would be needed.

For the isothermal pressure-volume coefficient dV/dP (at constant temperature), we differentiate V with respect to P, treating T as a constant:

dV/dP = bT

In conclusion, the isobaric expansion coefficient and the isothermal pressure-volume coefficient are bp - 2cT and bT, respectively, although the expansion coefficient is not purely in terms of coefficients b and c due to the presence of temperature T in the expression.

User Brahmana
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