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.
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Answer:
<u>The temperature difference is</u> 
Explanation:
The formula that is to used is :
Δ
Δ
<em>where ,</em>
- <em>Δ
is the heat supplied in calories = 300cal</em> - <em>
is the mass of water taken = m (assumed)</em> - <em>Δ
is the change in temperature</em> - <em>
is the specific heat of water =
</em>
ΔT :

Answer:
The maximum mass of carbon dioxide that could be produced by the chemical reaction is 70.6gCO_{2}
Explanation:
1. Write down the balanced chemical reaction:

2. Find the limiting reagent:
- First calculate the number of moles of hexane and oxygen with the mass given by the problem.
For the hexane:

For the oxygen:

- Then divide the number of moles between the stoichiometric coefficient:
For the hexane:

For the oxygen:

- As the fraction for the oxygen is the smallest, the oxygen is the limiting reagent.
3. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction:
The calculations must be done with the limiting reagent, that is the oxygen.

Answer:
hope it helps you...
Explanation:
acid rain is harmful for crop,and soil.