In the previous problem, what is the correct numerical value of R, and what are its units?

Previous problem

Let μ, which is called the molar mass, stand for the mass of 1 mole of gas expressed in kilograms, so that it has the units of kg/mol, as opposed to M in the previous chapter, which has the units of kg/mol. Thus, for example, for the O₂ molecule μ is 32 × 10⁻³ kg/mol. Show that υ_rms = (3RT/μ)^1/2.