Chapter 1.3 Flashcards
The three main steps in a mole calculation
- Find the number of moles of everything possible
- Use the chemical equation to work out the number of moles of the quantity required
- Convert moles to the required quantity
Formula for solving moles questions involving masses
m1/n1M1 = m2/n2M2
m1 = mass of first substance
n1 = coefficient of fist substance
M1 = molar mass of first substance
Yield
The amount of desired product
Formula to calculate percentage yield
% yield = actual yield divided by theoretical yield
Ideal gas
A concept invented by scientists to approximate the behavior of real gases
Two assumptions made when defining the ideal gas
The molecules themselves have no volume
No forces exist between the molecules
When do gases deviate most from ideal behavior?
When there is high pressure and low temperature
True or false? Volume of gas is proportional to the number of moles of the gas
True
Avogadro’s Law
Equal volumes of ideal gases measured at the same temperature and pressure contain the same number of molecules
STP meaning and values
Standard temperature and pressure, 273K, 100kPa
Molar volume
The volume occupied by one mole of a gas under certain conditions
Molar volume of an ideal gas at STP
22.7 dm^3 per mol or 2.27*10^(-2) m^3 per mol
What is a change of 1 degree Celsius equal to in kelvin?
1K
What is the equivalent of 0 degrees Celsius in kelvin?
273K
Formula for solving moles questions involving volumes of gases
m1/n1M1 = V2/n2Mv
m1 = mass of first substance
n1 = coefficient of first substance
M1 = molar mass of first substance
V2 = volume of second substance
Mv = molar volume of a gas
Alternative formula for solving moles questions involving volumes of gases if a volume is given and a volume is required
V1/n1 = V2/n2
V1 = volume of first substance
n1 = coefficient of first substance
Boyle’s Law
At a constant temperature, the volume of a fixed mass of an ideal gas is inversely proportional to its pressure
Charles’ Law
The volume of a fixed mass of an ideal gas at constant pressure is directly proportional to its kelvin temperature
Relationship between pressure and temperature
For a fixed mass of an ideal gas at constant volume, the pressure is directly proportional to its absolute temperature
Overall gas law equation
P1V1/T1 = P2V2/T2
Ideal gas equation
PV = nRT
The set of units needed for the ideal gas equation
R = 8.31 J per kelvin per mol
Pressure = N per m^2 or Pa
Volume = m^3
Temperature = K
Solute
A substance that is dissolved in another substance
Solvent
A substance that dissolves another substance
Solution
The substance that is formed when a solute dissolves in a solvent
Concentration
The amount of solute dissolved in a unit volume of solution
Relationship between concentration, number of moles and volume of solution
Concentration = number of moles divided by volume
Relationship between concentration, mass and volume
Concentration = mass over volume
Titration
A technique for finding the volumes of solutions that react exactly with each other
Equation for solving moles questions involving solutions
c1v1/n1 = c2v2/n2
c1 = concentration of first substance
v1 = volume of first substance
n1 = coefficient of first substance
