Name: potassium permanganate
* IUPAC
CAS Number: 7722-64-7
Chemical Formula: KMnO₄
Molar Mass: 158.033949 g
Mass Percent: K 24.740 %; Mn 34.763 %; O 40.496 % 

• inorganic

• "Bleaching resins, waxes, fats, oils, straw, cotton, silk and other fibers and chamois skins; dyeing wood brown; printing fabrics; washing CO₂ in manuf[acturing] mineral waters; exterminating Oidium tuckeri; photography; tanning leathers; purifying water; with formaldehyde sol[utio]n to expel formaldehyde gas for disinfecting; as an important reagent in analytical and synthetic organic chemistry." 1

• "Oxidation [in chemical water analysis]" 2

• "Potassium permanganate is one of the most important oxidizing agents.

Potassium permanganate is used in the preparation of many organic compounds, where it is employed as an oxidizing agent. Potassium permanganate is also used commercially as a disinfectant, as an air purifier, and for waste water treatment. The compound is used in chemical analysis to determine the amount of certain reducing compounds." 3

Density (g/cm3):
2.7 at room temperature/pressure 4
* - 1 atm pressure

Qualitative:
reacts:  4

10 FeSO4 (aq) + 2 KMnO4 (aq) + 8 H2SO4 (aq) → 5 Fe2(SO4)3 (aq) + 2 MnSO4 (aq) + 1 K2SO4 (aq) + 8 H2O (ℓ) 8
5 H2O2 (aq) + 2 KMnO4 (aq) + 3 H2SO4 (aq) → 5 O2 (g) + 2 MnSO4 (aq) + 1 K2SO4 (aq) + 8 H2O (ℓ) 8
5 Cr2(SO4)3 + 6 KMnO4 + 16 H2O → 10 H2CrO4 + 6 MnSO4 + 3 K2SO4 + 6 H2SO4  
6 HCl (aq) + 2 KMnO4 (aq) + 5 NaNO2 (aq) → 2 MnCl2 (aq) + 2 KCl (aq) + 5 NaNO3 (aq) + 4 H2O (ℓ) 
6 HNO3 (aq) + 5 H2C2O4 (aq) + 2 KMnO4 (aq) → 10 CO2 (g) + 2 Mn(NO3)2 (aq) + 2 KNO3 (aq) + 8 H2O (ℓ) 
2 KMnO4 (aq) + 3 KCN (aq) + H2O (ℓ) → 2 MnO2 (s) + 2 KOH (aq) + 3 KOCN (aq) 

Wikipedia

(1) - The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals, 13th ed.; Budavari, S.; O'Neil, M.J.; Smith, A.; Heckelman, P. E.; Kinneary, J. F., Eds.; Merck & Co.: Whitehouse Station, NJ, 2001; entry 7740.
(2) - Hammer, Mark J. Water and Wastewater Technology, 2nd ed.; Prentice Hall: Englewood Cliffs, NJ, 1986; p 9.
(3) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; pp 534-535.
(4) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4-77.
(5) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(6) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(7) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(8) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 137.