# The molecular mass of albumin is 60 kDa. What is the concentration of a 1.2 % m/m solution of albumin in milligrams per millilitre? What is the molar concentration?

##### 1 Answer

The concentration of albumin is a)

#### Explanation:

A dalton (**Da**) is simply another name for a unified atomic mass unit (**u**).

Thus, an atomic mass of 60 Da is the same as a mass of 60 u.

A molecular mass of 60 kDa is the same as a mass of 60 000 u.

The question is really saying that the molar mass of albumin is 60 000 g/mol.

**a) Concentration in milligrams per millilitre**

A 1.2 % (m/m) solution contains 1.2 g of albumin in 100 g of solution.

Since the solution is so dilute, we can assume that its density is 1.00 g/mL.

The concentration of albumin is 12 mg/mL.

**b) Concentration in terms of molarity**

The concentration of albumin is