Exam 2 Stoich and gas laws

 How many moles of nitrogen are needed to react with 6 moles of hydrogen?

N₂ +  3H₂ → 2NH₃

• 6 moles

• 2 moles

• 3 moles

• 1 mole

2H₂   +   O₂  →  2H₂O
How many moles of water can be produced if 16.2 grams H₂ are used?

• 4 moles
• 8 moles
• 16 moles
• 2 moles

Balance the following Reaction: Mg + Fe₂O₃ → MgO + Fe; What is the Ratio of moles of Fe₂O₃ to moles Fe?

• 3mol Fe₂O₃ / 2 mol Fe

• 2 mol Fe₂O₃/ 3 mol Fe

• 1 mol Fe₂O₃/ 2 mol Fe

• 2 mol Fe₂O₃ / 1 mol Fe

Cl₂ + 2KBr → Br₂ + 2KCl
How many grams of potassium chloride (KCl) can be produced from 356 g of potassium bromide (KBr)?

• 749 g
• 223 g
• 479 g
• 814 g

CH₄ + 2 O₂ → CO₂ + 2 H₂O
How many moles of carbon dioxide are produced from the combustion of 110 g of CH₄?

• 13.7 mol
• 2.75 mol
• 6.11 mol
• 6.85 mol

B₂H₆ + 3O₂ -->2 HBO₂ + 2 H₂O
 What mass of O₂ will be needed to burn 25.2 g of B₂H₆?

• 13.8 g O₂
• 9.71 g of O₂

• 125.2 g O₂
• 87.4 g O₂

When does a chemical reaction stop?

• When the lab is finished
• When the excess reactant is used up
• When the limiting reactant is used up
• Chemical reactions never stop

Identify the limiting reagent when 6.00 g HCl combines with 5.00 g Mg to form MgCl₂.
 
Mg +  2HCl --> MgCl₂  +  H₂   
 

• Mg
• H2
• MgCl2
• HCl

Using the following equation:
Fe₂O₃(s) + 3H₂(g) → 2Fe(s) + 3H₂O(l)
How many moles of iron can be made from  6 moles H₂? 

• 4 moles Fe
• 6 moles Fe
• 9 moles Fe
• 2 moles Fe

Fe (s) + S (l) --> FeS (s)  

In the experiment above, 7.62 g of Fe are allowed to react with 8.67 g of S.
How much FeS is formed? (HINT: find LR first)

• 14.8 g
• 12.2 g
• 13.7 g
• 19.9 g