Hello. My chemistry homework is due in 1 hour. I continue to get this question wrong time and time again. Please help me as soon as possible please!!

Question

Question 1:

2 NH3 + 3 CuO g 3 Cu + N2 + 3 H2O

In the above equation how many grams of N2 can be made when 158 grams of CuO 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

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Question 2:

3 Cu + 8HNO3 --> 3 Cu(NO3)2   + 2 NO + 4 H2O

In the above equation how many grams of water can be made when 6 grams 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

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please help me

Answer 1

Good afternoon, Greg. Both of these problems can be solved using three-step stoichiometry. Here is how the first problem can be solved:

Step 1: convert grams of CuO to moles of CuO

Step 2: convert moles of CuO to moles of N₂

Step 3: convert moles of N₂ to grams of N₂

The problem can be set up as follows:

(158g CuO) X (1mol CuO / 79.5g) X (1 mol N₂ / 3 mol CuO) X (28g / 1 mol N₂) = _____g N₂

I will let you do the calculation.

The same method can be used to solve the other problem.

Hopefully that helped...