Stoichiometry

What is the molecular formula if the empirical formula is CH₂O and the molecular molar mass is 180.18?

• CH₂O
• C₂H₄O₂
• C₄H₈O₄
• C₆H₁₂O₆

How many moles are in 16.94g of water?

• 16.94 mol H₂O
• 0.9401 mol H₂O
• 305.3 mol H₂O
• 1.063 mol H₂O

How many molecules are in 9.44 moles of aluminum chloride?

• 5.68 molecules AlCl₃
• 5.68x10²⁴ molecules AlCl₃
• 0.705 molecules AlCl₃
• 1.25x10²³ molecules AlCl₃

Tags

NGSS.HS-PS1-7

How many molecules are in 2.5 mol of sodium chloride?

• 1.51x10²³
• 146
• 4.15
• 1.51x10²⁴

What is the mass percentage of carbon in carbon dioxide?

• 27.3%
• 42.9%
• 57.1%
• 72.7%

What is the molar mass of sodium?

• 11
• 22.990
• 45.98
• 3

What are the units for molar mass?

• grams
• amu
• grams/mole
• liters

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

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

N₂ +  3H₂ → 2NH₃ 
How many moles of hydrogen are needed to react with 2 moles of nitrogen?

• 6
• 2
• 3
• 1

Tags

NGSS.HS-PS1-7