R134a..Here "a" is used to denote that it is an isomer. R134 and R134a have same chemical formula and atomic weight but different chemical structures.
R134 has NBP of about -19 C whereas R134a has a NBP of about -26C.
And dont use capital 'A' in R134a …. "A" denotes that the refrigerant is non -azeotropic.
