Vocabulary
molecular mass
calculates the mass of a molecule using the average mass of atoms
What is the formula mass for this compound, CaO?
Report answer to 4 significant figures!
56.08 g
2 H2 + O2 --> 2 H2O
If 9.0 moles of hydrogen react, how many moles of water are formed?
9.0 mol H20
What is Avogadro's number?
6.022 x 1023
What does percent composition describe?
the mass percentage of an element in a compound
molar mass
measures a mole quantity of a compound
What is the formula for this compound, CuCl2?
Report answer to 4 significant figures!
134.5 g
2 H2 + O2 --> 2 H2O
If 12.0 moles of oxygen react, how many grams of water are formed?
432 g H2O
Convert 10.0 moles of potassium to particles.
6.02 x 1024 particles
What is the formula for percent composition?
percent composition of one element = (mass of one element/mass of compound) x 100%
What do reaction coefficients describe?
the proportions of molecules present in a reaction
What is the formula for this compound, H2O?
Report answer to 4 significant figures!
18.02 g
2 H2 + O2 --> 2 H2O
If 27.4 grams of hydrogen react, how many grams of water are formed?
249 g H2O
Convert 40.0 grams of sodium to particles
1.05 x 1024 particles
CH4
What is the mass percentage of carbon in this compound?
25.132 u
stoichiometry
describes the ratio of reactants consumed and products produced; expressed by reaction coefficients
What is the formula for this compound, NaC2H3O2?
Report answer to 4 significant figures!
82.03 g
4 Fe + 3 O2 --> 2 Fe2O3
If 65 grams of iron react, how many grams of iron (III) oxide are formed?
93 g Fe2O3
How many moles of iron are in 8.32 x 1025 particles of iron?
138 mol Fe
NO2
What is the mass percentage of oxygen in this compound?
69.553%
limiting reagent vs. excess reagent
limiting reagents are completely consumed in a reaction and limit the amount of product formed
excess reagents are not completely consumed in the reaction, meaning some is leftover
What is the formula for this compound, Ba(OH)2?
Report answer to 4 significant figures!
171.3 g
4 Fe + 3 O2 --> 2 Fe2O3
If 49.3 grams of oxygen react, how many grams of product are formed?
164 g Fe2O3
How many grams of lithium are in 4.21 x 1026 particles of lithium?
4.85 x 103 g Li
C6H12O6
What is the mass percentage of hydrogen in this compound?
6.714%