Cards Flashcards
Mass per periodic table
Mass increase down a group and the number of energy levels increases by 1 down a group
Empirical Formula of an ionic compound
Is the same as the formula compound
Hydrates
Compounds that have a specific number of water molecules attached to them
To find how many water molecules
We can heat the compound, the difference between the initial mass and the mass of the anhydrous compound is equal to the mass of water
Relation between coefficients and moles
They are equivalent (2 H2O = 2 moles)
Limiting Reactant
The substance that controls the quantity of product that can form in a chemical reaction
Theoretical yield
The maximum amount of product that can be produced from a given amount of reactant
Factors that may cause the experimental yield to be lower
- Loss of products during purification
- An incomplete reaction
- Side reactions occurring
Factors that may cause the experimental yield to be higher
- Impurities in a product
- A product hasn’t been fully dried
Percentage yield
experimental yield/theoretical yield x 100
% atom economy
MM of Desired Product / MM of All Products x 100
Solute vs. Solvent
Solute : What is dissolved in a solution(salt)
Solvent : What dissolves the solute(water)
Concentration unit
mol dm-3 OR g dm-3
Molar concentration formula
c=n/v
Procedure for Preparing a Solution
- Accurately measure the mass of a solute
- Pour some distilled water to the volumetric flask
- Carefully add the solid to the flask
- Swirl the flask until all of the solute is dissolved
- Add the liquid solvent until it reacher the meniscus
- Place a cover on the flask and invert it back and forth to mix it
Moles in a solution vs diluted solution
The moles of the solute stay the same, adding more solvent
Concentration and volume equation
C1V1 = C2V2
Serial dilution
The process of diluting a sample several times
Spectrophotometry
Measurement of the absorption of electromagnetic radiation of a substance at different wavelengths of the spectrum
Using to determine the concentration of coloured solutions
Interpolating on a graph
Titration
A measured amount of a solution of unknown concentration is added to a known volume of a second solution until the reaction between them is just complete (neutralized)
End point vs equivalence point
End point - experimental
Equivalence point - theoretical
Avogradros law
States that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules and moles
Volume vs mole
Proportional - as the number of particles of gas increase, the volume does if the pressure and temp are constant
Ideal Gases
The volumes of the particles are barely anything compared to the volume that the gas occupies (spaces between particles are very large)
There are no intermolecular forces except when the particles collide
