Stoichiometry

What is the most important piece of information necessary to perform a stoichiometric calculation?

• Number of moles

• Number of particles

• Liters of gas

• Mass of reactants

• A balanced chemical equation

Tags

NGSS.HS-PS1-7

Four students tried to balance the following Reaction:

Mg + Fe₂O₃ → MgO + Fe

Which student is correct?

• 3Mg + Fe₂O₃ → 3MgO + 2Fe

• Mg + Fe₂O₃ → MgO₃+ Fe₂

• 2Mg + Fe₂O₂ → 2MgO + 2Fe

• 3Mg + 2Fe₂O₃ → 3MgO + 2Fe

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-7

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

2Al + 3H2SO4 -> Al2(SO4)3 + 3H2How many grams of aluminum sulfate would be formed if 250g H2SO4 completely reacted with aluminum?

• 0.85 g

• 290 g

• 450 g

• 870 g

How many moles of KBr will be produced from 7 moles of BaBr₂?
BaBr₂ + K₂SO₄ → KBr + BaSO₄

• 1 mole KBr
• 7 moles KBr
• 14 moles KBr
• 3.5 moles KBr

How many grams of bromine are required to react completely with 37.4 grams aluminum chloride?
AlCl₃ + Br₂ → AlBr₃ + Cl₂

• 33.6 g
• 134.5 g
• 29.9 g
• 67.2 g

6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂ 
What is the total number of moles of water needed to make 2.5 moles of C₆H₁₂O₆?

• 2.5
• 6
• 12
• 15

Tags

NGSS.HS-PS1-7

Use the following equation:

2Al + 3Cl2 → 2AlCl3

If 140 grams of aluminum chloride react, how many moles of aluminum will be produced?

• 5.10 moles of Al

• 1.05 moles of Al

• 2.25 moles of Al

• 3.42 moles of Al

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