Answer:
There are 3 sig figs
Explanation:
Sig figs are the amount of figures counting from the left side of the number until you reach the first zero. Starting from the left, I counted one, three, and six. That's 3 numbers, and therefore, that's how we got our answer. The only exception is when there is a decimal. Then all the numbers before the decimal, despite whether or not they're zeros, are sig figs.
The answer is C because you don’t have to worry about the number in front of the decimal unless it is something greater than zero. A- Doesn’t have there sig figs. B- The zero after the 5 doesn’t change it. D- The three at the end doesn’t matter because it does not round it up.
Answer:
Four possible isomers (1–4) for the natural product essramycin. The structure of compound 1 was attributed to essramycin by 1H NMR, 13C NMR, HMBC, HRMS, and IR experiments.
Explanation:
Three synthetic routes were used to prepare all four compounds (Figure 2A). All three reactions utilize 2-(5-amino-4H-1,2,4-triazol-3-yl)-1-phenylethanone (5) as the precursor, whereas each uses different esters (6–8) to construct the pyrimidinone ring. Isomer 1 was prepared by reaction A, which used triazole 5 and ethyl acetoacetate (6) in acetic acid. This was the reaction used in syntheses of essramycin by the Cooper and Moody laboratories.3,4 Reaction B produced compound 2 (minor product) and compound 3 (major product), which were separated chromatographically. This reaction allowed reagent 5 to react with ethyl 3-ethoxy-2-butenoate (7) in the presence of sodium in methanol, under reflux for 24 h. Compound 4 was prepared by reaction C, which was obtained by reflux of 5 and methyl 2-butynoate (8) in n-butanol.
Answer:
a. Solar
Explanation:
Solar energy causes water to evaporate, which is the driving force of the water cycle. Water from the ocean evaporates and comes back down as rain and it gives life to the Earth and so it continues.