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 2.1 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 14.1 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

3. 2 NH3 + 3 CuO → 3 Cu + N2 + 3 H2O

In the above equation, how many grams of N2 can be made when 16.7 moles 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 16

4. 2 NH3 + 3 CuO --> 3 Cu + N2 + 3 H2O

In the above equation how many moles of N2 can be made when 160.9 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

16

Answer 1

1. To solve for the grams of water produced, we need to use stoichiometry. First, we need to convert 2.1 moles of HNO3 to moles of water. From the balanced equation, we can see that for every 8 moles of HNO3, 4 moles of water are produced. Therefore, for 2.1 moles of HNO3:

• 2.1 moles HNO3 x (4 moles H2O/8 moles HNO3) = 1.05 moles H2O

Next, we can use the molar mass of water to convert moles to grams:

• 1.05 moles H2O x 18 g/mol = 18.9 g

Rounded to the nearest tenth, the answer is 18.9 grams of water.

2. Similarly, we need to use stoichiometry to find the grams of water produced. For 14.1 moles of HNO3:

• 14.1 moles HNO3 x (2 moles H2O/6 moles HNO3) = 4.7 moles H2O

• Converting moles to grams using the molar mass of water:

• 4.7 moles H2O x 18 g/mol = 84.6 g

Rounded to the nearest tenth, the answer is 84.6 grams of water.

3. To find the grams of N2 produced, we need to first convert 16.7 moles of CuO to moles of N2. From the balanced equation, we can see that for every 3 moles of CuO, 1 mole of N2 is produced. Therefore, for 16.7 moles of CuO:

• 16.7 moles CuO x (1 mole N2/3 moles CuO) = 5.56 moles N2

• Next, we can use the molar mass of N2 to convert moles to grams:

• 5.56 moles N2 x 28 g/mol = 155.7 g
  Rounded to the nearest tenth, the answer is 155.7 grams of N2.

4. To find the moles of N2 produced, we need to first convert 160.9 grams of CuO to moles. From the molar mass of CuO, we can see that 1 mole of CuO weighs 79.5 g.

• 160.9 g CuO x (1 mole CuO/79.5 g) = 2.02 moles CuO

• From the balanced equation, we can see that for every 3 moles of CuO, 1 mole of N2 is produced. Therefore, for 2.02 moles of CuO:

• 2.02 moles CuO x (1 mole N2/3 moles CuO) = 0.673 moles N2

Rounded to the nearest tenth, the answer is 0.7 moles of N2.

Answers:

1. 18.9 grams of water

2. 84.6 grams of water

3. 155.7 grams of N2

4. 0.7 moles of N2