Universal gas constant R= Cp-Cv

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Sabra_a
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Homework Statement
1) Using the first law of thermodynamics ∆Q=∆E+∆W (Q – heat added to the system, E – internal energy of the system, W – work done by the system), the equation of state for one mole of gas PV=RT (P - pressure, V – volume, R - universal gas constant, T - temperature), and the definition of the specific heat c=∆Q/∆T derive the following equation for universal gas constant: R= cp- cv (cp and cv are specific heats at constant pressure and constant volume correspondingly).

2) The specific heats ratio or adiabatic exponent is equal by definition to k= cp/cv. Derive formulas which express specific heats at constant pressure and constant volume (cp and cv) in terms of R and k only.
Relevant Equations
First law of thermodynamics
Ideal gas equation
Specific heat
In the first question should I remove the delta and put d or that doesn't make a difference and on the second question should I substitute the values of R, K, Cv and Cp or that's not required I'm not really sure how correct is my answer to the second question
Handwritten derivation of R = Cp - Cv from the first law of thermodynamics, followed by expressions for Cp and Cv in terms of R and K, with K = Cp/Cv and Cp = Cv K.
 
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  • Handwritten-style typed derivation of Cp and Cv in terms of R and K: from the first law ΔQ = ΔE + ΔW and PV = RT, it reaches R = Cp − Cv, then substitutes K = Cp/Cv to obtain Cv = R/(K − 1) and Cp = R·K/(K − 1).
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