`"pKa of trimethylamine " = 9.81`

9.81

The pKa of Trimethylamine constant displays the pKa of the conjugate acid for trimethylamine (9.81). 

The Math / Science

The pKa value of a compound indicates that strength of an acid. The pKa is the negative log base ten of the Ka value, also known as the acid dissociation constant. An efficient way to quantify basicity of an amine is to study the pKa of its conjugate acid. The conjugate acid is the compound formed when the acid donates a proton (H+) to a base. Note that the higher the pKa value of the conjugate acid, the stronger the base is.