Chemistry 6.5: Calculate Molarity From Moles and Volume
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There are 4 general types of calculations that are
used for molarity. The first equation is for
finding molarity when the amounts of solute and
solvent are known. S______ can be in either
grams or moles, s_______ can be in either liters
or milliliters.
Solutes can be in either g______ or m______,
solvents can be in either l______ or m_________.
In this illustration, the solute and solvent are
known amounts, and can be used to determine
m________.
The capital letter “M” means m___________, or
moles per liter of solvent.
A 1 M solution has 1 m________ of a substance
dissolved in enough solvent to equal 1000 ml
(1L).
A 2 M solution has 2 m________ of a substance
dissolved in enough solvent to equal 1000 ml
(1L).
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1 M NaCl has 58.443 grams dissolved in enough
solvent to equal 1 liter. 2 M NaCl has 116.886
grams dissolved in enough solvent to equal 1 liter.
Each description indicates its m_________.
Molar concentration is a description of a
solution’s m__________.
The upper case letter “M” is the symbol for
m_________.
The equation shown in the illustration is used to
calculate the molarity of a molar solution.
M________ is equal to the number of moles of
solute divided by the volume of the solution
measured in liters.
Molarity is equal to the n_______ of m_______
of solute divided by the l______ of s________.
In this problem, the student is asked to calculate
the m________ of a solution.
Step one in solving this type of problem is to find
the molar mass of the solute, expressed as a mole
or part of a mole. The molar mass of 1 mole of
NaCl is ________.
2
The solution has 9 grams of NaCl. To find the
number of moles of the solute, divide the amount
in the solution by the 1 mol molar mass. The
number of moles of the solute in the problem is
______ NaCl.
The next step is to divide the moles of NaCl by
the liters of solution. The molarity of the solution
in the problem is ________ NaCl.
In this problem, the student is asked to calculate
the m________ of a solution.
Step one: find the m______ m_____ of the
solute, CaCl2. The molar mass of 1 mole of CaCl2
is ________.
The solution has 100 grams of CaCl2. To find the
number of moles of the solute, divide the amount
in the solution by the 1 mol molar mass. The
number of moles of the solute in the problem is
______ CaCl2.
Step 2: this problem gives the amount of solvent
as 500 ml. 500 ml must be converted to liters.
500 ml is converted to _______ L.
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Step 3: the next step is to divide the moles of
CaCl2 by the liters of solution. The molarity of
the solution in the problem is ________ CaCl2.
In this problem, the student is asked to calculate
the m________ of a solution.
Step one: find the m______ m_____ of the
solute, C12H22O11. The molar mass of 1 mole of
C12H22O11 is ________.
Step 2: the solution has 513.4447 grams of
C12H22O11. To find the number of moles of the
solute, divide the grams in the solution by the 1
mol molar mass. The number of moles of the
solute in the problem is ________ C12H22O11.
Step 3: the next step is to divide the moles of
C12H22O11 by the liters of solution. The molarity
of the solution in the problem is ________
C12H22O11.
Review
Solutes can be in either g______ or m______,
solvents can be in either l______ or m_________.
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The capital letter “M” means m___________, or
moles per liter of solution.
A 1 M solution has 1 m________ of a substance
dissolved in enough solvent to equal 1000 ml
(1L).
A 2 M solution has 2 m________ of a substance
dissolved in enough solvent to equal 1000 ml
(1L).
Molarity is equal to the n_______ of m_______
of solute divided by the l______ of s________.
Step one: find the m______ m_____ of the
solute.
Step 2: find the number of m____ of the solute
by dividing the grams in the solution by the 1 mol
molar mass.
Step 3: divide the number of m____ of solute by
the l_____ of solution.
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