Stoichiometry

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

Tags

NGSS.HS-PS1-7

2 NaClO₃ (s) --> 2NaCl (s) +3 O₂ (g)  
12.00 moles of NaClO₃ will produce how many grams of O₂?

• 256 g of O₂
• 576 g of O₂
• 288 g O₂

Tags

NGSS.HS-PS1-7

What is the limiting reactant if 10 moles of NH₃  react  with 30.0 moles of NO?
4NH₃+6NO --> 5N₂ + 6H₂O

• NH₃
• NO
• N₂
• water

Tags

NGSS.HS-PS1-7

2Na + 2H₂O → 2NaOH+ H₂
How many grams of hydrogen are produced if 120 g of Na are available?

• 5.2 g
• 2.6 g
• 690 g
• 45 g

Tags

NGSS.HS-PS1-7

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?

• 14.8 g
• 12.2 g
• 13.7 g
• 19.9 g

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

Tags

NGSS.HS-PS1-7

When two substances react to form products, the reactant which is used up is called the_____.

• excess reactant
• limiting reactant
• catalytic reactant
• determining reactant

Tags

NGSS.HS-PS1-7

What can be determined from a balanced chemical equation?

• Mole ratio of any two substances in the reaction
• Energy released in the reaction.
• Electron configuration of all elements in the reaction. 
• Mechanism involved in the reaction. 

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-7

Lead nitrate can be decomposed by heating.  What is the % yield of the decomposition reaction if 7.4g Pb(NO₃)₂ are heated to give 4.1 g PbO?
2Pb(NO₃)_{2 (s)}→2PbO_(s)+4NO_2(g)+O_2(g)

• 82%
• 44%
• 56%
• 67%

Tags

NGSS.HS-PS1-7

What is the empirical formula for a compound containing: 92.30% carbon and 7.70% hydrogen

• CH
• CH₄
• C₂H₄
• C₂H₄