Stoichiometry Unit Test

Metallic sodium reacts violently with water to form hydrogen and sodium hydroxide according to the following equation. 
2Na + 2H₂O→2NaOH + H₂
How many moles of hydrogen gas are generated when 4.0 moles of sodium react with excess water?

• 1 mole H₂
• 2 moles H₂
• 3 moles H₂
• 4 moles H₂

Tags

NGSS.HS-PS1-7

Consider this reaction:
3Ca(s) + 2H₃PO₄ (aq) → Ca₃(PO₄)₂ (s) + 3H₂ (g)
How many moles of calcium are required to produce 60.0 g of calcium phosphate?

• 0.145 mole
• 0.194 mole
• 0.387 mole
• 0.581 mole

Tags

NGSS.HS-PS1-7

According to the equation: 
2 H₂O (l) → 2H₂(g) + O₂ (g)
What mass of H₂O is required to yield 22.4 L of O₂ at STP?

• 12g
• 18g
• 24g
• 36g

Consider this reaction:
3 Mg (s) + 2 H₃PO₄ (aq)
 → Mg₃(PO₄)₂ (s) + 3H₂ (g).
How many grams of magnesium phosphate should be produced if 5.40 grams of magnesium react with excess phosphoric acid?

• 1.80 grams
• 19.5 grams
• 58.4 grams
• 175 grams

Tags

NGSS.HS-PS1-7

Methane (CH₄) is burned in oxygen according to this balanced chemical equation:
CH₄(g) + 2 O₂ (g) → CO₂ (g) + 2H₂O (g)
What volume of carbon dioxide is formed when 9.36 liters of methane are burned in excess oxygen at STP?

• 9.36 L
• 15.0L
• 18.7 L
• 22.4 L

What is the volume of 2.00 moles of nitrogen gas (N₂ ) at STP?

• 11.2 L
• 28.0 L
• 44.8 L
• 56.0 L 

How many formula units are in 2.5 mol of NaCl?

• 1.51x10²³

• 146

• 4.15

• 1.51x10²⁴

How many molecules of sugar (C₆H₁₂O₆) are in a mole?

• 24 molecules
• 180 molecules
• 180 g
• 6.02 x 10²³ molecules

Fluorine is diatomic.  What is the molar mass of fluorine gas?

• 18.998 g/mol
• 37.996 g/mol
• 9 g/mol
• 18 g/mol

Always starts with a Hydrocarbon that reacts with oxygen and produces carbon dioxide and water. 

• Decomposition
• Synthesis
• Combustion
• Single Replacement

Tags

NGSS.HS-PS3-4