What are the references for?
1) Propionic, ethanoic and butanoic acid
2) Methane
3) Carbon dioxide
4) Ammonia
1) The references for propionic, ethanoic, and butanoic acid are likely to be sources that provide information on these specific organic acids. This may include scientific articles, textbooks, or chemical databases that explain their properties, uses, reactions, and other relevant information.
2) The references for methane are sources that provide information on this specific hydrocarbon compound. These sources may include scientific literature, textbooks, or databases that discuss methane's physical and chemical properties, sources and emissions, global warming potential, applications, and other related topics.
3) The references for carbon dioxide are sources that provide information on this specific gas. These sources may include scientific papers, textbooks, or databases that cover carbon dioxide's role in the environment, greenhouse gas emissions and climate change, carbon cycle, industrial uses, chemical reactions, and other relevant aspects.
4) The references for ammonia are sources that provide information on this specific compound. This may include scientific literature, textbooks, or databases that discuss ammonia's properties, production methods, uses in industries such as agriculture and manufacturing, reactions, toxicity, and other related topics.