Stochiometry

What is the mass of 1 atom of copper in amu?

• 58.933
• 2.37 x 10^-21
• 63.546
• 51.995

What is the mass of 4 copper atoms in g?

• 254.2 g
• 2.37 x 10²¹ g
• 6.022 x10²³ g
• 4.22 x10^–22 g

Tags

NGSS.HS-PS1-7

What is the molar mass of ethanol (C₂H₅OH)?

• 45.06 g/mol
• 34.06 g/mol
• 46.07 g/mol
• 30.03 g/mol

An oxide of iron has the formula Fe₃O₄. What mass percent of iron does it contain?

• 72%
• 28%
• 30%
• 0.72%

Tags

NGSS.HS-PS1-7

A hydrocarbon (a compound consisting solely of carbon and hydrogen) is found to be 85.6% carbon by mass. What is the empirical formula for this compound?

• CH
• CH₂
• C₂H
• CH₄

Balance this equation using the smallest possible integers, NO + NH₃ --->N₂ +  H₂O.  What is the coefficient of the water?

• 1
• ²
• 4
• 6

• Bread
• Cheese
• Lettuce
• Meat