Question

An aqueous solution of 10.00 g of catalase, an enzyme found in the liver has a volume of 1.00 L at 27⁰C. The solution’s osmotic pressure at 27⁰C is found to be 0.745 torr. Calculate the molar mass of catalase.

Short answer

The molar mass of catalase is 2.51 x 10⁵ g/mol.

Step-by-step solution

Step 1- Given data

The mass of catalase (m)= 10.0 g

The volume of catalase (V)= 1 L

The temperature (T)= 27 ⁰C

The osmotic pressure of the solution (P)= 0.745 torr

The gas constant (R)= 0.08206 atm/K.mol

Step 2- Osmotic pressure

Formula for osmotic pressure is P=MRT

Substituting the given values

0.745 torr (1atm/760 torr) = M X 0.08206 L atm /K.mol X (27C + 273 )K

M= 0.000980263/24.618 L. atm/mol

= 39.818 X 10^-06 mol/L

Step 3- calculating number of moles

Number of moles of catalase=

M=n/v so n= M X V

n= 39.818 X 10^-06 mol/L X 1L

= 39.818 X 10^-06 mol

Step 4- Calculating molar mass of catalase

M=m/n

= 10g/39.818 X 10^-06 mol

= 2.51 X 10⁵ g/mol