Ch.8 Chemical Composition Flashcards
how to calc average mass?
avg mass=total mass / number
how much does 1 atomic mass unit weigh?
1 atomic mass unit (amu)=1.66 x10^-24 g
from numbers to amu’s (mass of element)
multiply by atomic mass
from amu’s (mass of element) to numbers
divide by the atomic mass
what is avogardos number
1 mol= 6.022 x 10 ^23 particles
what does the definition of the mole give us a
relationship between mass and number of atoms
the mole is equal to the number of atoms in
12.01 grams of pure carbon
12.01 g C = 1 mol C atoms=6.022 x10^23 particles
what is molar mass?
the mass in grams of one more of a substance
molar mass is numerically equal to what?
mass in atomic mass units
units of molar mass are
grams per mole
from numbers to moles
divide by 6.022 x 10 ^23
from mole to numbers
multiply by 6.022 x 10 ^23
from moles to grams
multiply molar mass
from grams to moles
divide by molar mass
from numbers to moles divide by
avargados #
from moles to numbers
multiply by avaragados #
molar mass of a substance is the
grams per mole of its entities
what is monatomic elements?
the molar mass is the same as the atomic mass in grams per mole
empirical formula
the simplest formula for a compound that agrees with the elemental analysis
what does empirical formula show?
it shows the lowest whole number of moles and gives the relative number of atoms of each elect present
molecular formula
the formula of a compound as exists showing the actual number atoms of each element in a molecule of a compound
the molecular formula is always an integer multiple of the empirical formula units:
molecular formula=(emperical formula)n
what does molar mass equal?
formula wise
molar mass=n x empirical formula mass
