Amount of Substance (P1, P2, P3) Flashcards
Define Ar, the relative atomic mass
The weighted average mass of an atom of an element, taking into account it’s naturally occurring isotopes, relative to 1/12 mass of an atom of carbon-12.
Define Mr, the relative molecular mass
The mass of a molecule compared to 1/12 of the mass of an atom of carbon-12.
What is the Avogadro constant? And how do you use it in a calcultaion?
6.022x10^23
Actual number of atoms = moles x Avogadro
Moles/Mass/Mr equation
Mass = Mr x Moles
Concentration Equation
Concentration = Moles/Volume
What is Boyle’s law?
The product of pressure and volume is a constant as long as temperature remians constant.
Pressure x Volume = Constant
What is Charles’s law?
The volume is proportional to the temperature as long as the pressure remains constant.
Volume ∝ Temperature
Volume/Temperature = Constant
What is Gay-Lussac’s law?
The pressure is proportional to the temperature as long as the volume remains constant.
Pressure ∝ Temperature
Pressure/Temperature = Constant
(Pressure x Volume)/Temperature = Constant for a fixed mass of gas
The ideal gas equation
Pressure x Volume = Number of moles x temperature x gas constant
Pressure - Pa Volume - m3 Number of moles - n Temperature - K Gas Constant = 8.3 JK^-1 mol^-1
How do you convert from degrees celsius to kelvin?
+273
How do you calculate Empirical Formula?
- Find the masses of each element
- Find the moles of each element
- Find the simplest ratio
How do you calculate Molecular Formula?
Mr of compound/Empirical Formula’s Mr
Acid + Metal Oxide
Salt + Water
Acid + Metal Carbonate
Salt + Water + Carbon Dioxide
Acid + Metal Hydroxide
Salt + Water
