Transcript Physical Science Fall 07 Review

7. Chemical Reactions
Chemical Reactions
How many atoms of each element are
found in Na2SO4?
Chemical Reactions
How many atoms of each element are
found in Na2SO4?
Na= 2
S=1
O=4
Chemical Reactions
How many atoms of each element are
found in Ba(OH)2?
Chemical Reactions
How many atoms of each element are
found in Ba(OH)2?
Ba = 2
O=2
H=2
Chemical Reactions
How many atoms of each element are
found in (NH4)3PO4
Chemical Reactions
How many atoms of each element are
found in (NH4)3PO4
N=3
H= 12
P=1
O=4
Chemical Reactions
In a chemical reaction the substances
on the left of the  are called
____________ and the substances on
the right are called __________ .
Chemical Reactions
In a chemical reaction the substances
on the left of the  are called
reactants and the substances on the
right are called products .
Chemical Reactions
In chemical reactions ________ speed
up a reaction and _________ slow
down a reaction.
Chemical Reactions
In chemical reactions catalysts speed
up a reaction and inhibitors slow
down a reaction.
Chemical Reactions
In a combustion reaction, oxygen (O2)
reacts with another substance to
produce _____ and ______.
Chemical Reactions
In a combustion reaction, oxygen (O2)
reacts with another substance to
produce carbon dioxide (CO2) and
water (H2O)
Chemical Reactions
In a combustion reaction, oxygen (O2)
reacts with another substance to
produce carbon dioxide (CO2) and
water (H2O)
Chemical Reactions
Balance the following reaction:
AlBr3 + K  KBr + Al
Chemical Reactions
Balance the following reaction:
AlBr3 + 3K  3KBr + Al
Chemical Reactions
What type of reaction is this?
AlBr3 + 3K  3KBr + Al
Chemical Reactions
What type of reaction is this?
Al is displaced and Br binds to
potassium: Single displacement
AlBr3 + 3K  3KBr + Al
Chemical Reactions
Balance the following reaction:
CH4 + O2  CO2 + H2O
Chemical Reactions
Balance the following reaction:
CH4 + 2O2  CO2 + 2H2O
Chemical Reactions
What type of reaction is the following
reaction?
CH4 + 2O2  CO2 + 2H2O
Chemical Reactions
What type of reaction is the following
reaction?
Oxygen gas reacts to produce carbon
dioxide and water: combustion.
CH4 + 2O2  CO2 + 2H2O
Chemical Reactions
What type of reaction is the following
reaction?
Bi + F2  BiF3
Chemical Reactions
What type of reaction is the following
reaction?
Two substances form ONE, more
complex substance. synthesis
Bi + F2  BiF3
Chemical Reactions
Balance the following reaction.
Bi + F2  BiF3
Chemical Reactions
Balance the following reaction.
2Bi + 3F2  2BiF3
Chemical Reactions
Balance the following reaction.
Al2O3  Al + O2
Chemical Reactions
Balance the following reaction.
2Al2O3  4Al + 3O2
Chemical Reactions
What type of reaction is this?
2Al2O3  4Al + 3O2
Chemical Reactions
What type of reaction is this?
A compound breaks down into two
simpler compounds; decomposition
2Al2O3  4Al + 3O2
Chemical Reactions
What type of reaction is this?
A compound breaks down into two
simpler compounds; decomposition
2Al2O3  4Al + 3O2
Chemical Reactions
What type of reaction is this?
FeO + PdF2  FeF2 + PdO
Chemical Reactions
What type of reaction is this?
Ions switch places.
Double displacement
FeO + PdF2  FeF2 + PdO
Chemical Reactions
Balance the reaction?
FeO + PdF2  FeF2 + PdO
Chemical Reactions
Balance the reaction?
FeO + PdF2  FeF2 + PdO
It IS balanced
Chemical Reactions
When there is a net release of energy
during a chemical reaction (usually in
the form of heat) it is __________,
but if energy is absorbed and the
temperature decreases it is ________.
Chemical Reactions
When there is a net release of energy
during a chemical reaction (usually in
the form of heat) it is exothermic , but
if energy is absorbed and the
temperature decreases it is
endothermic.
Chemical Reactions
_____ ______ is the minimum amount
of energy needed to start a chemical
reaction.
Chemical Reactions
Activation energy is the minimum
amount of energy needed to start a
chemical reaction.
Chemical Reactions
Which of the following is NOT true of
a mole?
contains 6.02 x 1023 particles of a
substance
b. atomic number of an element is equal
to its molar mass.
a.
c.
d.
is represented by Avogadro’s number
mole ratios cannot be determined in a
chemical reaction
Chemical Reactions
Which of the following is NOT true of
a mole?
contains 6.02 x 1023 particles of a
substance
b. atomic number of an element is equal
to its molar mass.
a.
c.
d.
is represented by Avogadro’s number
mole ratios cannot be determined in a
chemical reaction
Chemical Reactions
What is the molar mass of one mole of
Argon?
Chemical Reactions
What is the molar mass of one mole of
Argon?
Find argon (Ar) on the periodic table.
The atomic mass equals one molar
mass = 40 g/mol
Chemical Reactions
What is the mass of 2 moles of
carbon?
Chemical Reactions
What is the mass of 2 moles of
carbon?
Find carbon (C) on the periodic table.
The atomic mass equals one molar
mass = 12 g/mol
2 mol C x 12 g C / 1 mol C = 24 g C
Chemical Reactions
What is the mass of 1 mole of sodium
chloride (NaCl)?
Chemical Reactions
What is the mass of 1 mole of sodium
chloride (NaCl)?
Element
Atoms of
element
Molar mass
Total mass for element
Na
1
X
23
=
23
Cl
1
X
35
=
35
Sum of masses 58 g/mol NaCl
Chemical Reactions
What is the mass of 1 mole of sodium
chloride (CaCO3)?
Chemical Reactions
What is the mass of 1 mole of sodium
chloride (CaCO3)?
Element
Atoms of
element
Molar mass
Total mass for element
Ca
1
X
40
=
40
C
1
X
12
=
12
O
3
x
16
=
48
Sum of masses 100 g/mol CaCO3