Unit two Flashcards
When do covalent bonds occur
when electrons are shared between atoms; between nonmetals
When do ionic bonds occur
when electrons are gained or lost; between metals and nonmentals
what is electronegativity
the tendency of an atom to attract electron density towards itself
What is the electronegativity trend
increases up and to the right
How do you figure out formal charge
separate electrons based on how they are shared then determine if each element has more valence electrons than usual
how do you find percent composition
number of moles in molecule times mass number divided by the smallest of those numbers
How do you go from empirical formula to molecular formula
Must be given molar mass then divide that by empirical mass and multiple by empirical formula
How do you go from percent composition to empirical formula
Assume the percents are out of 100 grams so given percentages are grams, divide by mass number then by smallest number to get formula
what is the formula for molality
mols of solute divided by kg of solution
What is the formula for molarity
mol of solute over liters of solution
What is the formula for percent by mass
mass of solute over total mass times 100
What is the formula for percent by volume
volume of solute over total volume time 100
What is the formula for mass per unit volume
mass of solute over total volume
what are the strong acids
halogens except for first and last, HNO3, H2SO4, and HCl4
what are the strong bases
LiOH, NaOH, KOH, Ca(OH)2, Sr(OH)2, and Ba(OH)2
What is the driving force of neutralization reactions
formation of salt and water
What are redox reactions
when an atom gains electrons while another loses electrons
What happens to electrons when an atom is oxidized
they lose electrons
what happens to electrons when an atom is reduced
they gain electrons
what is the oxidation number of covalent fluorine
-1
what is the oxidation number of covalent oxygen
-2
what is the oxidation number of covalent and ionic hydrogen
covalent is +1 and ionic is -1
What is an oxidation
increase in oxidation number
what is a reduction
decrease in oxidation number
What is an oxidizing agent
agent that causes oxidation while it is being reduced
what is a reducing agent
agent that causes reductions while it is being oxidized
What is percent yield
measure of how well the reaction went
What is the formula for percent yield
actual over theoretical times 100
