What is a
What is a
A mole is a counting
unit for _________.
That means 1 mole of
atoms =
?
?
Example:
A
things = _____ things
So a
apples is
apples.
How to use
or the same as
?
Example:
or the same as
which is the same
number written in
______________
________________.
If I have 36 items, how many
dozens do I have? 36 ÷ 12 = 3 dozen
If I have 2 dozen items, how many
items do I have? 2 x 12 = 24 items
between
and
12.04 x 10²³ atoms
= 2 moles
4 moles
= 24.08 x 10²³ atoms
Part 1: Convert moles to atoms
a) 1 mole =
______________________ atoms
b) 2 moles =
______________________ atoms
c) 6 moles =
______________________ atoms
d) 2.9 moles =
______________________ atoms
e) 10.2 moles =
______________________ atoms
Part 2: Convert atoms to moles
a) 36.12 x 10²³ atoms =
______________________ moles
b) 6.9 x 10²³ atoms =
______________________ moles
c) 6.02 x 1030 atoms =
______________________ moles
d) 6.02 x 10 10 atoms =
______________________ moles
e) 8.03 x 10 50 atoms =
______________________ moles
What is
?
The mass of 1 _____________ of atoms is called the molar mass.
The mass of an atom is the relative ____________ __________ and can
be found on the _______________ _______________ of elements.
Different ______________ have different molar masses. The units for
molar mass are _________ per __________ or
Example:
A
of carbon = _____ grams
Draw twelve beans in cup 1, twelve penne pasta in cup two and twelve
peanuts in cup 3.
Do you think each cup will weigh the same? Why or why not?
You will weigh each cup and write the mass of the dozen things under
each cup.
Cup 1
Weight: ____g
Cup 2
Weight: ____g
Cup 3
Weight: ____g
Just like 12 of each of these foods weigh different amounts,
different atoms weigh differently.
Atomic
number
3
The relative_____________
___________ found on the
periodic table shows the mass of
the atom compared to carbon.
This number is also the molar
mass measured in
Atomic
symbol
Lithium
6.94
.
Atom name
Relative
Atomic mass
Instructions: Complete the table below using your periodic
table.
Element
symbol
Element
name
Atomic
number
Atomic
mass
Molar mass
Na
Sodium
11
23
23 g/mol
K
Mn
Argon
Helium
12
20
30
Au
Xenon
53
What is a
?
The mass of 1 _____________ of a
A
is a unit
meaning one
compound like
CO2 or one
diatomic species
like O2
is called the
formula mass.
Formula mass and molar mass
have the __________ unit which
is:
The mass can be found by
adding the molar mass of each
_________ in the molecule.
H2O (water)
Find the number of atoms for each element.
Find the atomic mass or molar mass for each element.
Multiply the atomic mass or molar mass by the
number of atoms of that element.
Add all the masses for all elements together.
Write the unit.
H = 2 atoms
O = 1 atom
H= 1.01 g/mol x 2 = 2.02 g/mol
O = 16 g/mol x 1 = 16 g/mol
2.02 + 16 = 18.02 g/mol of H2O or water
CO2
C = 1 atom
O = 2 atoms
C= 12.01 g/mol x 1
O = 16 g/mol x 2
= 24.02 g/mol
= 32 g/mol
24.02 + 32 = 56.02 g/mol of CO2
Find the formula mass using the periodic
table and your instructions.
a) H2
b) H2O2
c) CH4
d) SO2
e) NaCl
f) KBr
g) C6H12O6
h) Mg(OH)2
i) AlPO4
j) Al(NO3)3
Cover the
measurement you
want to find then
use the remaining
formula
What is the mass of 2 moles of
Sodium (Na)?
Moles x Molar mass = Mass
Molar mass of Na = 23 g/mol
2 moles x 23 g/mol = 46 grams
How many moles are there in
48 grams of Carbon (C)?
Mass ÷ Molar mass = Moles
Molar mass of C = 12 g/mol
48 g ÷ 12 g/mol = 4 moles
Complete the able below using your
formula triangle and periodic table, pay attention to which
values you have been given.
Chemical
formula
Formula used
Molar mass
Mass
(grams)
Ar
50
Li2O
62
Moles
Ca S
9.1
NO3
0.5
AlCl3
210
V2O5
96
BeF2
4.5
Fe2O3
12
Sr(OH)2
900
Pb(NO3)2
6