Other Flashcards
For first ionization’s energy what is the value of n
n= Z
For 2nd, 3rd… ionization energies what is the value of n
n = coefficient of e-config after how ever many electrons have been removed
How many electrons do you remove for the first, second, third ionization’s
First = 1 e
Second = 2 e
Third = 3 e
Formula for percent yield
% yield = (actual yield/ theoretical yield) (100)
Wavelength formula
Lambda = c/v
How to solve if given wavelength and n, asked for element
1) given lambda, so E=hc/lambda
2) E = Z^2(Rh)/n , solve for Z and associate with an element
Steps for determining limiting reactant (2)
(If moles not given)
1) convert all masses to moles (if moles not given)
2) divide each mole value by their corresponding coefficient
smaller #= limiting reactant
What does “what mass of the product CAN BE FORMED mean”
you have to determine the limiting reactant BEFORE you can do stoich calculations
How to solve “what mass of the product can be formed questions” (2)
1) determine limiting reactant
2) use stoich formula to determine number of miles of product formed, but replace initial reactant with limiting reactant
(moles of limiting reactant)(coeff of column wanted)/ (coeff of limiting reactant)
Formula for n
n = m/M
Stoich formula (in moles)
(Initial of first reactant)(coeff of column wanted)/ (coeff of first column)
How to calculate percent dissociation for acids when given ph
Raise 10 to the negative power of the pH for the value of the “amount dissociated”
(Amount dissociated)/(original amount in moles) (100)
What does for in chemical formula mean
Multiply molar mass of that compound by that coefficient
Steps for finding unknown coeff of multiplication formula (4)
1) find total M of compound
2) subtract all M’s from elements WITHOUT unknown coeff
3) determine total M of elements with UNKOWN coeff
4) divide number in step 2 by number in step 3 to obtain coeff
Formula for vapour pressure
Vapour pressure =
(mol frac of solvent)(vapour press of solvent)
What is usually constant in the vapour pressure formula and why
Vapour pressure of solvent
Will most likely be comparing hydrates (contain water) so the vapour pressure of the solvent will be the same for both
Formula for mol fraction
mol fraction =
(mole of the thing)/(total moles of the compound)
Molecular formula
Ratio size and use
Larger ratio
Used to see HOW MANY of the elements are in that compound
Empirical formula
Ratio size and use
Smaller ratio
Used to see WHAT ELEMENTS are in that compound
What do you have to do when question says “smallest mass determinable for a certain element”
Divide M of the element by Avagadro’s number
(M)/(Avagadro’s #)
Avagadro’s number definition
Number of units in ONE mole of any substance
Two purposes of structural formulas
Identify the location of chemical bonds between the atoms
Shows the order in which atoms are bonded together
What two charges can copper have
+1 or +2
How to name ionic compounds
Add “ide” to end of no mental
How to name acids (begin with H)
2 elements:
Hydro____ic acid
3 elements:
Ion ending in “ate” = ____ic acid
Ion ending in “ite” = _____ous acid
What is a desiccant substance
Hygroscopic substance used to induce a state of dryness
What does “stochiometric amount” mean
The amount that will react COMPLETELY with a given amount of another reactant, leaving NO EXCESS of either one
What is a hydrate
The water of a hydrate is usually present in ____ amounts
Any compound contains water
Stoichiometric amounts
What is hygroscopic
Compounds that tend to ABSORB water
what does heating a hydrate do to its water
Drives it off
(Because of evaporation)
What is effloresce
Spontaneous loss of water by a hydrated salt
