Hello please help me with my chemistry please someone respond please

Question

1.) 3 Cu + 8HNO3 → 3 Cu(NO3)2  + 2 NO + 4 H2O

In the above equation, how many grams of water can be made when 4.3 moles of HNO3 are consumed?

Round your answer to the nearest tenth. If you answer is a whole number like 4, report the answer as 4.0

Use the following molar masses. If you do not use these masses, the computer will mark your answer incorrect:

Element   Molar Mass

Hydrogen   1

Nitrogen   14

Copper   63.5

Oxygen   16

2.) S  + 6 HNO3 → H2SO4 + 6 NO2 + 2 H2O

In the above equation, how many grams of water can be made when 7.4 moles of HNO3 are consumed?

Round your answer to the nearest tenth. If you answer is a whole number like 4, report the answer as 4.0

Use the following molar masses. If you do not use these masses, the computer will mark your answer incorrect.:

Element   Molar Mass

Hydrogen   1

Nitrogen   14

Sulfur       32

Oxygen   16

please please just solve and explain

Answer 1

Hi Jess,

Let me know if I was able to answer your question.

For part one of the problem, I began by calculating the quantity of water produced by the reaction in moles. This is done using simple ratios. The ratio of HNO3 molecules to H2O molecules can be determined by looking at the coefficient of each of these molecules. In this case, the ratio of HNO3 to H2O is 8:4, which can be simplified to 2:1. Thus, for every 4.3 moles of HNO3 that are consumed, half of that amount (2.15 moles) of H2O is produced. This number can easily be converted into grams by using the molar mass of water. To do so, we must first determine the molar mass of water. Your instructor did not provide this information, but they did provide the molar mass of oxygen (16 grams per mol) and the molar mass of hydrogen (1 gram per mol). As one molecule of water consists of one molecule of oxygen and two molecules of hydrogen, the molar mass of water can be determined by adding 16 + 1 + 1, to get the answer of 18. Finally, you can multiple the molar mass of water (18 grams per mol) by the amount of water produced in moles (2.15 moles) to reach an answer of 38.7 grams of water.

The second part of the problem follows relatively the same process. In this case, the ratio of molecules of HNO3 to molecules of H2O is 6:2, which can be simplified to 3:1. Thus, if 7.4 moles of HNO3 are consumed, 2.467 moles of H2O are produced. To convert this quantity to grams, we must once again multiple by the molar mass of water (18). This yields us a rounded result of 44.4 grams.