Why might nitrogen monoxide (NO) concentrations decrease as the day progresses?
A) Morning rush hour traffic has ended.
B) Plant photosynthesis starts when the sun rises.
C) Solar energy causes the reactions that consume NO.
D) The organisms that produce NO are anaerobic and there is more oxygen in the morning.
E) I don't NO.
Question 2
The elements of Group VIIIA are almost entirely non-reactive with any of the other chemical elements. Which of the following statements best explains this observed behavior?
A) Group VIIIA elements comply with the octet rule.
B) Group VIIIA elements are so rare that no one has ever studied their reactive properties in any detail.
C) Group VIIIA elements are all gases, and gases are generally non-reactive.
D) No explanation given here can explain why Group VIIIA elements do not react with any of the other chemical elements.
Nitrogen trioxide
The Last 10,000 Years of Greenhouse Gas Concentrations
Pathways of nitrogen metabolism (purple) in the general pattern of intermediary metabolism
The nitrogen cycle "دورة النيتروجين"
Soil is a crucial part of the nitrogen cycle
Decrease in mean haplotype heterozygosity