Gas Laws (No Calculations)
What is something that makes gases different than solids and liquids?
Indefinite volume
Low Densities
Particles in constant random motion
What is the volume of 1 mole of gas at STP?
22.41L
2H2 + O2 → 2H2O
If we have 10 moles of Hydrogen gas and 4 moles of Oxygen gas, which is the limiting reactant?
Oxygen (O2)
2H2 + O2 → 2H2O
What is the mole ratio of Oxygen gas to Hydrogen gas?
1O2 : 2H2
The coefficients of a balanced chemical equation tell us what?
Mole Ratio
What data point is the Kelvin temperature scale based on?
Absolute Zero (0K)
If 15L of CO2 are kept at a pressure of 5atm and a temperature of 300K, how many moles of CO2 are present?
3.05 mols
If the theoretical yield of a reaction was 25g Sodium Hydroxide but students collected 27g when running the experiment in lab, what is their percent yield?
108%
4Al + 3O2 → 2Al2O3
How many moles oxygen are needed to react with 20 moles of aluminum?
15 mols O2
What conversion factor is needed to convert from liters of solution to moles of solute?
Molarity
What does STP stand for and what are the STP values?
Standard Temperature & Pressure
0oC or 273K
1atm
If the pressure of a 21L sample of oxygen gas drops from 5atm to 1.5atm, what is the new volume of the gas sample?
70L
4Al + 3O2 → 2Al2O3
If we have 50 grams each of Aluminum and Oxygen gas, what is the limiting reactant?
Aluminum
2C2H6 + 7O2 → 4CO2 + 6H2O
If 15 moles of oxygen react, how many grams of water will be formed?
231.7g H2O
Where can you find the values for theoretical yield and actual yield?
Theoretical yield = calculate using stoich
Actual yield = measured in lab or given in question
If the temperature of a set volume of gas increases, what happens to the pressure of that gas?
Pressure increases
If 4.5x1025 molecules of nitrogen gas are at STP, what volume of space would they occupy?
1675.39L
2C2H6 + 7O2 → 4CO2 + 6H2O
20g C2H6 is burned in excess oxygen. If this experiment was run in a lab and 55g of CO2 was collected, what is the percent yield?
94%
2HCl + Ca(OH)2 → 2H2O + CaCl2
If 250mL of 1.5M HCl reacts with excess Ca(OH)2, what is the mass of calcium chloride produced?
20.81g CaCl2
What determines how much product can actually be produced by any given chemical reaction?
Limiting Reactant
What is the Ideal Gas Law Constant? (Must include correct unit)
0.0821 (L*Atm)/(mol*K)
A gas originally has a temperature of 27oC, a pressure of 2atm, and a volume of 6L. If the temperature increased by 60oC and the pressure increased to 2.4atm, what is the volume of this gas?
6L
If 30 moles of both nitrogen gas and hydrogen gas react to form ammonia (NH3), how much excess reactant is left over after the reaction has finished?
20 mol N2 excess
2H2 + O2 → 2H2O
If 50g of oxygen reacted with 10 grams of hydrogen, what is the theoretical yield of water in grams?
56.31g H2O
MEMORY TEST
What was the precipitate that you created in the percent yield lab? (Name or Formula)
Copper Hydroxide or Copper II Hydroxide
Cu(OH)2