VOCAB
Equations must be balanced to obey this law
The law of conservation of mass
How many moles of potassium (K) are in 3.04 grams of pure potassium metal?
0.0778 mol K
2 KClO3 ---> 2 KCl + 3 O2 1.50 mol of KClO3 decomposes. How many grams of O2 will be produced?
72.0 g O2
LiOH + HBr --->LiBr + H2O If you start with 10.0 grams of lithium hydroxide, how many grams of lithium bromide will be produced?
36.3 g LiBr
HgO ----> Hg+O2 How many moles of mercury are produced if 24.5 moles of mercury (II) oxide decompose? Balance the equation first!
24.5 moles
What is the molar ratio in a chemical equation?
The ratio of moles of one substance to moles of another
2 KClO3 ---> 2 KCl + 3 O2 If 80.0 grams of O2 was produced, how many moles of KClO3 decomposed?
1.67 mol
2 H2 + O2 ---> 2 H2O How many grams of H2O are produced when 2.50 moles of oxygen are used?
90 g H2O
Mg + 2 NaF--->MgF2 + 2 Na If you start with 5.5 grams of sodium fluoride, how many grams of magnesium fluoride will be produced?
4.1 g MgF2
4NH3+5O2 --->4NO+6H2O How many moles of oxygen are needed to react with 4.6 moles of ammonia
5.8 moles
What is molar mass?
Mass of one mole of a substance
Given 12 g of aluminum, how many moles do you have?
0.44 mol Al
How many grams are 10.78 moles of Calcium (Ca)?
432.0 g Ca
C2H4 + 3 O2--->2 CO2 + 2 H2O If you start with 45 grams of ethylene (C2H4), how many grams of carbon dioxide will be produced?
140 g CO2
2 KClO3 ---> 2 KCl + 3 O2 How many moles of O2 can be produced by letting 12.00 moles of KClO3 react?
18.00 mols
What is a mole?
A mole is a counting unit, equal to 6.02 x 1023 particles
Given 25 g of NaCl, how many moles do you have?
0.43 mol NaCl
2 H2 + O2 ---> 2 H2O If 3.00 moles of H2O are produced, how many grams of hydrogen gas must be used?
6.05 g H2
2 HCl + Na2SO4--->2 NaCl + H2SO4 If you start with 20 grams of hydrochloric acid, how many grams of sulfuric acid will be produced?
30 g H2SO4
Cu + 2 AgNO3 ---> Cu(NO3)2 + 2 Ag How many moles of Cu are needed to react with 3.50 moles of AgNO3?
1.75 moles
What is Stoichiometry?
The calculation of quantitative relationships of the reactants and products in a balanced equation
Given 125 g of H2SO4, how many moles do you have?
1.27 mol H2SO4
Given 0.345 mol of water, how many grams would you have?
6.22 g H2O
Pentane C5H12 reacts with oxygen gas to produce carbon dioxide and water. How many grams of carbon dioxide will be produced by the reaction of 108.0 grams of pentane?
329.4 g CO2
4 NH3 (g) + 5 O2 (g) ---> 4 NO (g) + 6 H2O (l) When 1.20 mole of ammonia reacts, the total number of moles of products formed is:
3.00 moles total