Why oxygen gas is environmentally friendly than ammonia gas

How do you identify the anode on a power source such as a battery? how do you identify the cathode? how are terms anion and cation?

Why do lunar and solar eclipse not happen every month

Need what is special about water as a compound? how does water regulate climate? what drives water evaporation?   why is the water vapor fresh water when it rises from the ocean? why might freshwater in the form of snow take longer to enter the water cycle again than liquid precipitation?   what is an aquifer? what role do people play in the water cycle? plz just answer as many as you can ! thx if you !