2h2(g)+o 2(> 2 h2o(g)if eight moles of hydrogen react how many of moles of water are produced and how many moles of oxygen are required

As shown in the equation the molar ratio of H2 to H20 is 1:1, therefore if 8 moles of H2 are used, 8 moles of H2O are produced. However the molar ratio of H2 to O2 is 2:1 therefore the number of moles of O2 required is 8/2 = 4.

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$8,566

Explanation:

The computation of the gross margin is shown below:

Purchase of inventory$9,800

Less: Purchase discount ($9,800 × 2%)  ($196)

Add: Freight paid$430

Total purchase made$10,034

Sales$18,600

Gross margin ($18,600 - $10,034)$8,566

We simply deduct the sales from the total purchase so that the gross margin amount could come