LAB 2 Flashcards
empirical formula
chemical formula that represents the relative number of atoms in a compound (the simplest mole ratio)
molecular formula
the chemical formula that gives the actual number of atoms in a compound
example with hydrogen peroxide
empirical: HO
molecular: H2O2
how can we determine the empirical formula of a compound
through measuring the mass of each component in a compound
Hydrate
hydrates have a specific number of water molecules associated with each formula unit
what does the raised dot represent when writing out hydrate formulas
the “weak” bond between the anhydride and the number of water molecules (also called water of hydration)
Hydrates and Anhydrous compounds have
- distinct diff physical and chemical properties
- ability to gain/lose water makes them versatile
Percent composition formula of water
% of water= (mass of h2o/original mass of compound) times 100
In the reaction between Copper and Magnesium, what is the reaction and which is the oxidizer and reducer
Redox reaction, H2O over yield arrow
- occurs between copper ions and solid mg
- will help us convert Cu ions to Copper solid
- transfer electrons from Mg to Cu ions to form solid Cu and Mg ions
Mg- reducer, being oxidized
Cu- oxidizer, being reduced
how can we track the progress of the reaction
the disappearance of the blue colour from copper ions
how can we ensure complete displacement of Copper
- adding excess Mg
- supply hydrogen ions from HCl to force the reaction in the forward direction (SINCE HCl and Cu have NO RXN)
the secondary reaction between Mg and H is responsible for
production of Hydrogen gas
how can we determine the mass of the third component, chlorine
mass cl= mass sample-mass h2o-mass cu
how can we determine molecular formula
- if we know the molecular mass
hydrate is an
ionic compound
