Molar Mass
The molar mass is useful when converting between _______________ and ______________.
What is grams and moles?
This is the definition of a limiting reagent.
(Something like . . .)
What is the chemical that gets used up first in a reaction. It is the chemical that limits how much product you can make.
This is the equation for calculating percent yield.
Percent yield = (actual yield / theoretical yield) x 100
Diamonds are made primarily of this element.
What is carbon?
This is the rounded molar mass of Na.
What is 23 g/mole?
Without using any numbers or specific chemical names, this is the general procedure for going from n grams of substance X to an unknown number of grams of substance Y.
n grams of X divided by molar mass of X
multiply by mole ratio
multiply by molar mass of Y
If you're making ham sandwiches. Each sandwich needs 2 pieces of bread and one slice of ham. If you have 30 pieces of bread and 20 slices of ham, this is the limiting reagent.
What is the bread?
If you got 45 out of 50 possible questions right on a test, this was your % score.
90 %
This is the molar mass of Li2S.
What is 46 g/mole?
Fe2O3 + CO2 --> 2Fe + 3CO2
How much Fe2O3 is needed to obtain 92.8 g of Fe?
What is 133 g Fe2O3
2Cu + S --> Cu2S
This is the limiting reactant when 80 g of Cu reacts with 25 g of S.
What is copper?
What is H2O2
This is the molar mass of Na3PO4.
What is 164 g/mole?
2NaOH + CO2 --> Na2CO3 + H2O
This number of grams of CO2 are needed to react with 3.5 grams of NaOH.
What is 1.925 g CO2?
If you got 87% yield when you made 15.7 grams of a substance, what was your theoretical yield?
What is 18 g?
CaCO3 --> CaO + CO2
What is the theoretical yield of CaO if 24.8 g of CaCO3 is heated?
What is 13.9 g of CaO.
In the equation:
2Fe2O3 + C --> Fe + 3CO2,
this is the molar mass of carbon dioxide.
What is 44 g/mole?
SiO2 + 3C --> SiC + 2CO
When 50 g of silicon dioxide is heated with an excess of carbon, 32.2 g of silicon carbide is produced. How many grams of CO are made if it CO shows the same % yield?
N2H4 + O2 --> N2 + 2 H2O
You have 1,000 g of N2H4 and 1,400 g of O2.
How many grams of the excess reagent will remain after the reaction?
400 grams excess O2
1 - Determine the limiting reactant
2 - Use that limiting amount to determine how much of the excess is used.
3 - Subtract from the amount of excess reagent you began with.
FeCO3 + O2 --> 2Fe2O3 +4CO2
If 75 g of FeCO3 is heated with an excess of oxygen, 45 g of Fe2O3 is produced.
What is the percent yield of this reaction?
This element (which can be sold for as much as $68 million / gram) is often called the most expensive element.
What is Californium?