AIEEE Chemistry Unit 16C K2Cr2O7 and KMnO4

Potassium Dichromate and Potassium Permanganate

Syllabus

Preparation, properties and uses of K2Cr2O7 and KMnO4.

Potassium dichromate

K2Cr2O7.

It's molecular weight is 294.19 g/mol.
Melting point: 3980C.
Boiling point: 5000C

Potassium dichromate's state at room temperature is solid.
Potassium dichromate is ionic.
It's molecular geometry is tetrahedral.
Potassium dichromate is crystalline ionic solid with a red-orange color.

It's uses include dyeing, staining, tanning leather, as bleach, oxidiser, depolariser for dry cells, etc.

Medically it has been used externally as an astringent, antiseptic, and caustic.

It has also been used in photographic screening.
It is used as an anti-pain remedy in homeopathy.
It is used ini ethonal determination.

When taken internally, it is a corrosive poison. Hence it is poisonous and hazardous to health.


Potassium Permanganate
KMnO4

Molecular Weight- 158.03 g

Melting Point- 270°C

Boiling Point- Doesn't boil

State - at room temperature solid - Purple, sweet flavor, and crystals.

Ionic


Uses- disinfectant, propellant in rockets, and is used in torpedos.