en.wikipedia.org/wiki/Monochloramine
2 corrections found
Colorless gas
Authoritative references describe pure/anhydrous monochloramine as a liquid, not a gas.
Full reasoning
The infobox lists monochloramine's appearance as "Colorless gas", but authoritative chemical references describe pure monochloramine as a liquid.
- EPA's Drinking Water Criteria Document for Chloramines states that "Anhydrous monochloramine is a colorless, water-soluble liquid" and says it freezes at −66 °C.
- PubChem likewise describes chloramine as a "colorless to yellow liquid".
- The National Research Council's Drinking Water and Health also describes pure monochloramine as a colorless, unstable, and pungent liquid with a freezing point of −66 °C.
Those sources directly contradict the infobox entry calling it a gas.
3 sources
- Drinking Water Criteria Document for Chloramines
Anhydrous monochloramine is a colorless, water-soluble liquid ... that freezes at -66°C. The pure liquid decomposes above -50°C.
- Monochloramine | Cl.H2.N | CID 25423 - PubChem
Description: Chloramine is a colorless to yellow liquid with a strong pungent odor. (NTP, 1992)
- Chemistry and Toxicity of Selected Disinfectants and By-Products - Drinking Water and Health - NCBI Bookshelf
Pure monochloramine is a colorless, unstable, and pungent liquid with a freezing point of -66°C.
Due to its acidic nature,
Lead-release concerns from chloramination are not because monochloramine is acidic. Monochloramine is favored under neutral-to-alkaline conditions, and EPA describes lead issues as a water-chemistry/corrosivity problem.
Full reasoning
The phrase "Due to its acidic nature," gives the wrong reason for why switching to chloramine can sometimes worsen lead problems.
Authoritative drinking-water guidance does not describe monochloramine as an acidic disinfectant. Health Canada states that neutral to alkaline conditions (pH 6.5–9.0) are optimum for monochloramine formation, while acidic conditions favor dichloramine and trichloramine instead. EPA's monochloramine guidance explains lead concerns differently: chloramination can change water chemistry and make water more corrosive, which can increase lead release from plumbing in some systems.
So the broader point that chloramination can contribute to lead-release problems in some systems is real, but attributing that to monochloramine's supposed acidic nature is incorrect.
3 sources
- Chloramines in Drinking Water - Guideline Technical Document for Public Consultation - Canada.ca
Neutral to alkaline conditions (pH 6.5–9.0) are optimum for monochloramine formation ... whereas acidic conditions are optimum for the formation of dichloramine (pH 4.0–6.0) and trichloramine (pH <4.4).
- Common Health Questions Related to Monochloramine: Does monochloramine use change water chemistry? Does monochloramine use contribute to the release of lead or other contaminants into drinking water?
Changes in water chemistry from monochloramine use may impact lead or other contaminant levels ... Changes in water chemistry can make water more corrosive, which may lead to pipe corrosion ... and an increase in the release of lead or other contaminants into the water.
- Basic Information about Lead in Drinking Water | US EPA
Lead can enter drinking water when plumbing materials that contain lead corrode, especially where the water has high acidity or low mineral content that corrodes pipes and fixtures.