Solution Found!
Reviewing ConceptsAnswer the following true or
Chapter 3, Problem 146P(choose chapter or problem)
Answer the following true or false. Explain.
(a) For a gas modeled as an ideal gas, \(c_p=c_v+R\), where R is the gas constant for the gas.
(b) Air always can be regarded as a pure substance.
(c) Water at \(p=100 \mathrm{lbf} / \mathrm{in}^2\) and \(v=0.0169 \mathrm{ft}^3 / \mathrm{lb}\) is a compressed liquid.
(d) Atmospheric air is normally not modeled as an ideal
gas.
(e) For liquid water, the following approximation is reasonable for many engineering calculations: \(v(T, p)= v_{\mathrm{f}}(T)\).
Questions & Answers
QUESTION:
Answer the following true or false. Explain.
(a) For a gas modeled as an ideal gas, \(c_p=c_v+R\), where R is the gas constant for the gas.
(b) Air always can be regarded as a pure substance.
(c) Water at \(p=100 \mathrm{lbf} / \mathrm{in}^2\) and \(v=0.0169 \mathrm{ft}^3 / \mathrm{lb}\) is a compressed liquid.
(d) Atmospheric air is normally not modeled as an ideal
gas.
(e) For liquid water, the following approximation is reasonable for many engineering calculations: \(v(T, p)= v_{\mathrm{f}}(T)\).
ANSWER:Solution 146P:
Step 1 of 5:-
a)
For a gas modeled as an ideal gas, cp = cv + R, where R is the gas constant for the gas.
This is true.
We know that, .
And
We also know that, .
So, the 1st law of thermodynamics tells that,
(proved)