Is benzocaine water soluble?

Benzocaine is only slightly soluble in water. In the Merck Index (Merck & Co. 1989), its solubility is reported as 400 mg/L.

What are the properties of benzocaine?

Benzocaine is a colorless trapezial crystal. Its melting point is 92℃ (88-90℃), boiling point is 183-184°C (1.87kPa). 1g of this medicine is soluble in about 2500ml water, 5ml ethanol, 2ml chloroform, 4ml ether or 30-50ml almond oil and olive oil, and it is also soluble in dilute acid.

What is the pKa of benzocaine?

2.5
The pKa of benzoic acid is 4.2; the pKa of the conjugate acid of benzocaine is 2.5.

Why is benzocaine not soluble in water?

General DescriptionBenzocaine is a unique local anesthetic because it does notcontain a tertiary amine. The pKa of the aromatic amine is 3.5ensuring that benzocaine is uncharged at physiological pH. Because it is uncharged, it is not water soluble but is ideal fortopical applications.

Is benzocaine acidic or basic?

Benzocaine occurs in two forms: a crystalline salt (benzocaine HCl) that is soluble in water at 0.4 g/L, and a nonwater-soluble basic form that must be dissolved in ethyl alcohol at a concentration of 0.2 g/ml before it is sufficiently soluble in water to create a functional induction dose.

Is benzocaine a weak acid or base?

From the ladder diagram, we see that (a) at any pH greater than 9.1, benzocaine is present as its neutral weak base and pentobarbital is present as its anionic weak base, and that (b) at any pH less than 1.5, benzocaine is present as its cationic weak acid and pentobarbital is present as its neutral weak acid.