5-Methyl-1H-pyrazole-3-carboxylic acid

  • 3-Carboxy-5-methylpyrazole
Formula
C5H6N2O2
Structure
Description
White solid.

Registry Numbers and Inventories.
CAS
402-61-9
R: 36/37/38
S: 26 37/39
RTECS
UQ6407500
Merck
12,6194
Beilstein/Gmelin
2906
Beilstein Reference
4-25-00-00731

Properties.
Formula
C5H6N2O2
Formula mass
126.11
Melting point, °C
236 - 237
Boiling point, °C
389
Vapor pressure, mmHg
9.7E-7 (25 C)
Density
1.404 g/cm3
Solubility in water
Very soluble
pKa/pKb
4.05 (pKa)
Partition coefficient, pKow
0.25
Heat of vaporization
67.3 kJ/mol

Hazards and Protection.
Storage
Store in a cool, dry place. Store in a tightly closed container.
Protection
Wear appropriate protective gloves and clothing to prevent skin exposure. Use chemical protective goggles.
Respirators
Follow the OSHA respirator regulations found in 29 CFR 1910.134 or European Standard EN 149. Use a NIOSH/MSHA or European Standard EN 149 approved respirator if exposure limits are exceeded or if irritation or other symptoms are experienced.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container.
Incompatibilities
Oxidizing agents, reducing agents, bases, amines.
Decomposition
Nitrogen oxides, carbon monoxide, carbon dioxide, ammonia.

Fire.
Flash Point,°C
189
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Use water spray, dry chemical, carbon dioxide, or chemical foam to extinguish.

Health.
Exposure effects
   Ingestion
May cause irritation of the digestive tract. May be harmful if swallowed.
   Inhalation
Causes respiratory tract irritation. May be harmful if inhaled.
   Skin
Causes skin irritation. May be harmful if absorbed through the skin.
   Eyes
Causes eye irritation

First aid
 
   Ingestion
Get medical aid. Wash mouth out with water.
   Inhalation
Remove from exposure and move to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
Get medical aid. Flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.