Cv/Cp versus R

[chloewinnett1L]

When calculating ΔS, when should we use R and when should we use Cv and Cp, or (3/2)R and (5/2)R, respectively?

[Bijan Mehdizadeh 1B]

It depends what values you are given and which one(s) you need to find. However, R is only used in reversible isothermal reactions while C is used when temperature is changing, and you use Cv or Cp depending on whether volume or pressure are constant.

[Riley Dean 2D]

R is used for reversible reactions when temp is constant, usually like if you have deltaS=nRln(v2/v2), then use deltaS=nCvln(t2/t1) for a constant volume and a change in temp and then deltaS=nCpln(t2/t1) for a constant pressure and a change in temp

[Niveda_B_3I]

Cv is for when volume is constant, and Cp is used for when pressure is constant.

[Katelyn Phan 2A]

R is used in isothermal reactions whereas 3/2R and 5/2R are used in place of Cp or Cv where there is a temperature change.