exam II Flashcards
what is the shape of TeF4
trigonal bipyramidal
what is the molecular geometry of XeO3
trigonal pyramidal
how do you find the formal charge of an atom?
of VE – # of bonds – # of Individual lone pairs
how do you find the hybridization of an atom
count the number of bonds and lone pair GROUPS then count up to that number in spppddddd…
how do you find the percent by mass
atomic mass 1 / atomic mass 2
how do you find how many molecules are in something
g x (1 mol x/molar mass x) x 6.022x10^23
how do you find the amount of grams produced
x mol (1 mol y / 1 mol x) (molar mass x / 1 mol y)
how do you find the empirical formula
g of x/ molar mass of x; g of y / molar mass of y; divide by the smallest answer on both sides; multiply both sides by the same # to get a whole #.
describe the difference between molecular and ionic.
molecular bonds are between two nonmetals, and ionic bonds are between a metal and a nonmetal.
what are the semimetals
B, Si, Ge, As, Sb, Te, At
NH4
ammonium
Hg2^2+
mercury I
C2H3O2^-
acetate
CO3^2-
carbonate
ClO3^-
chlorate
CN^-
cyanide
HCO3^-
hydrogen carbonate
OH^-
hydroxide
ClO^-
hypochlorite
NO3^-
nitrate
ClO4^-
perchlorate
PO4^3-
phosphate
SO4^2-
sulfate
do nonmetals tend to lose or gain electrons?
gain
what is the charge of a Na ion and why?
+1, because it lost an electron
what makes Cl special?
it is a peripheral atom, meaning it can use the d orbital to bond, aka have more than 8 valance electrons/bonds
how do you find the formal charge of an atom?
ve of neutral atom - # of bonds - # of nonbonding electrons
what does one amu equal?
1.661 x 10^-24 g
how do you find the mol of 3.08g of CO2
(3.08g)(1mol/44.01g)= .07 mol
CO2
what are the angles of
AE2
AE3
AE4
AE5
AE6
linear
trigonal planar
tetrahedral
trigonal bipyramidal
octahedral
what is a sigma bond
a single bond
A naturally occurring sample of an element contains only two isotopes. The first isotope has a mass of 68.9255 amu and a natural abundance of 60.11%. The second isotope has a mass of 70.9247 amu. Find the atomic mass of the element.
(68.9255+70.9247)/2= 69.93
Determine the number of atoms in 1.85 mL of mercury. (The density of mercury is 13.5 g/mL.)
1.85(13.5)= 24.975 x 6.022x10^23= 1.5x10^25
A 20.0 g sample of an element contains 4.95 1023 atoms. Identify the element.
4.95x10^23(1 mol/6.022x10^23)= .822
20/.822= 24.33
Mg
Determine the number of CH2Cl2 molecules in 25.0 g of CH2Cl2
25 x 6.022x10^23= 1.51x10^25 moles
Which molecular geometry results when a central atom has five total electron groups (three bonding groups and two lone pairs)?
t shaped
Determine the mass of potassium in 35.5 g KBr
35.5/119= .298x39.26= 11.7
