01 Stoichiometry Flashcards
Mases tvermes desnis
The law of conservation of mass
Atom
Smallest particle of an elemnet to show the characteristic properties of that element
Native form
Pure elements that are uncombined with other elements in nature
Chemical compounds
Substances that exist in combinations with two or more other elements
Types of chemical reactions
Combustion
Decomposition
Precipitation
Displacement
Synthesis
All concepts of yield
Theoretical yield
Limiting reactant
experimental yield
Percentage yield (experim./theor. x 100%)
Atom economy
Atom economy (not yield) shows how much of the reactant ends up as the product (not waste).
The higher the economy, the more effective is the reaction, the less waste
Types of mixture
Homogenous: uniform composition
Heterogenous: non-uniform composition
Isotope
Isotope is an atom of the same element that has the same number of protons but different number of neutrons
Absolute temperature units
K
Absolute zero value
0 K
Kinetic theory of matter
av. KE of particles is directly related to temperature of the system
Diffusion
Diffusion is the process by which particled become evenly distributed as a result of their random movement
The higher the mass of particles, the slower they mix because KE=0.5mv^2 (v - velocity)
Relative atomic mass
Notation: Ar
no units!
Relative formule mass
Mr
no units!
Molar mass
M
g/mol
Avogadro’s law
equal volumes of all gases when measured at the same temperature and pressure contain an equal number of particles (occupy the same volume)
1 mol = 22.7 dm^3/mol at STP (T: 0C/ 273 K; P: 100 kPa)
V∝n at constant P and T
Avogradro’s constant notation
NA or L
Why ideal gas is ideal?
Chemical nature of ideal gas is irrelevant to its volume because the majority of volume in gas is empty space
Hydrated salt
Compounds that contain a fixed ratio of water molecules known as water of crystalisation
Opposite: anhydrous salt
1 bar =
1 atm =
1 bar = 10^5 kPa
1 atm = 101.325 kPa
Relationship between P, V and T
- V and P
Boyle’s law P∝1/V (pressure depends on volume) at constant T
Formula: P1V1/T1=P2V2/T2
- V and T
Charle’s law V∝T (volume tepends on temp - KE)
Formula: V/T=constant
- P and T
P∝T (pressure depends on temp - KE)
Formula: P/T=constant
Ideal gas equation
Ideal gas obeys PV=nRT
P at Pa
V at m^3
n at mol
T at K
R - universal gas constant (8.314 J mol^-1 K^-1)
ppm concept
ppm - unit of concentration (parts per million)
ppm=mass of component/total mass of solution x 10^6
Hard exercise with expression of reaction’s coefficient sum
Hard exercise with a graph that represents the relationship between Volume and pressure
