Which statement describes a process involved in the evolution of earth’s early atmosphere? - cyanobacteria transformed carbon dioxide in the atmosphere into oxygen during photosynthesis. - heavier gases escaped through earth’s atmosphere, leaving only lighter gases such as oxygen behind. - volcanic eruptions produced enough oxygen to create earth’s atmosphere. - the amount of oxygen in the atmosphere declined due to respiration, or breathing.
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Chemistry, 22.06.2019 14:50
Which of the following is most likely true about water in chemical systems? a) water dissolves nonpolar ionic compounds. b) water dissociates ionic compounds. c) water dissociates covalent molecules. d) water dissolves nonpolar covalent substances.
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Chemistry, 22.06.2019 21:00
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 !
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Chemistry, 23.06.2019 00:30
Element j is 1s 2s 2p 3s . (i) how many unpaired electrons does j have? (ii) is j a good oxidizing agent or a reducing agent? (iii) state reason for the answer.
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Chemistry, 23.06.2019 01:00
Which of the following is in the lanthanide family? a) uranium b) promethium c) silver d) gold
Answers: 2
Which statement describes a process involved in the evolution of earth’s early atmosphere? - cyanob...
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