Soil contains organic matter called humus. Humus is classified into humic and nonhumic materials. Humic materials are operationally divided into three main fractions:
Humic acid, fulvic acid, and humin.

Properties of Humic Materials.
Features Humic Acid Fulvic Acid Humin
Solubility in water soluble in alkaline pHs soluble at all pHs insoluble at all pHs
Aromatic content highly aromatic highly aromatic highly aromatic
Carboxylic acid content some high low
Phenolic content some some some

Humic materials
↓ HCl
soluble insoluble
↓ ↓NaOH
Fraction A soluble insoluble
↓ ↓
Fraction B Fraction C

In flowchart above, Fraction B is most likely:

a) Humic acid. b) Fulvic acid. c) Humin.

state the principle of separating two immiscible liquids by separating funnel. describe an activity with diagram to separate a mixture of water and kerosene oil. answer: immiscible layers separate out in layers depending on their densities in separating funne

explanation:

answer : (a) volume of the gas = 8.67 ×   l

                (b) second virial coefficient b = -1.21226 l/mole

solution :   given,     t = 300k

                                p = 20atm

                                z = 0.86

                                n = 8.2 mmoles = 8.2 × moles

                                r =   0.082 l atm/k/mol

        find,     (a) volume of gas   and (b) second virial coefficient b at 300k.

formula used :            

                          and            

(a)            

                    = \times 0.082\times 300}{20}[/tex]

                    = 8.67 ×   l

(b)      

                    = (0.00867-1) × 8.659

                    = - 8.5839 l/mole