Answer to Question #140302 in General Chemistry for Sohyun Ravena

Question

Description of the various prepared colloidal solution.

                                        Observations

Fe(OH)3sol

Calcium acetate gel

Benzene/water

without detergent

with detergent

Cigarette smoke

Answer 1

Fe(OH)3 sol :

Dispersion medium is liquid

and dispersed phase is solid.

Colour of sol is brown.

Calcium acetate gel :

Dispersion medium is solid

and dispersed phase is liquid (alcohol).

Colour of gel is white.

Benzene/water :

without detergent :

Dispersion medium is liquid

and dispersed phase is also liquid.

This type of colloid is called emulsion

Colour of emulsion is yellow

with detergent :

When detergent is added to the water- benzene colloid system, detergent assist benzene to coagulated forming a different phases as cloud concentration of detergent is low in such colloid.

With detergent the colloid forms a yellow precipitate.

Cigarette smoke :

Dispersion medium is gas

and dispersed phase is solid.

This type of colloid is called solid airosol.