TIMARU GIRLS’ HIGH SCHOOL
SCIENCE DEPARTMENT
Level 1 Science
AS 1.8/90947
Investigate Selected Chemical Reactions
Assessment – Internal
4 Credits
Specific Learning Outcomes
I can:
Describe the structure of an atom in terms of Protons, neutrons,
1
electrons, shells, atomic number and mass number
Write electron configurations for atoms
2
3
4
Discuss Chemical bonding in terms of electron loss/gain (ionic) or
sharing (covalent)
Relate metallic structure to physical properties of metals
Use the collision theory to describe factors which affect the rate of a
reaction
Identify precipitation reactions(exchange reactions) including naming
6
precipitates formed
Describe thermal decomposition reactions of carbonates and hydrogen
7
carbonates.
Describe the displacement of metal ions in solution in terms of simple
8
electron transfer
5
Topic 1: Atomic Theory
Matter is anything that has a mass and takes up space. Atoms are the basic unit of all
matter. Everything from YOU to the book you are writing in is made of atoms. Matter
has ______________________ and ________________________.
Phases of Matter
Matter exists in three different phases or states: ___________, ___________, ______
Solids
Liquid
Gas
All matter is in motion!!!
*Gas properties applet*
Classification of Matter:
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Atomic Theory:
Neils Bohr (1885-1962) – Bohr Model
 Electrons can only exist at certain
distances from the nucleus (called
orbits, shells, or energy levels)
Remember, all matter is made up of ATOMS!!!!
What are elements? Give two examples
Atom vs element??
Name the three subatomic particles that make up an element.
1.
2.
3.
Complete the following table:
Most of the
volume an
atom
Particle
Electron
Location
Charge
Proton
Most of
the mass
of an atom
Neutron
Draw a picture of a HELIUM atom including electrons, protons and neutrons.
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Periodic Table of Elements: Metal vs. Nonmetals
Groups
Periods
Lets look at a symbol on the periodic table:
11
Na
Sodium
22.99
Na+
Definitions:
Na + forms when Na loses 1
electron
Atomic Number:


Average Atomic Mass:

Isotopes:

Ex: Carbon-14 vs Carbon-12:
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Uranium-235 vs Uranium 238:
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Example: Fill in the chart below.
Summary of Atomic Structure:






3 subatomic particles: _____________, ____________, ______________
Protons and neutrons are in ____________
_____________ orbit the nucleus and have a negligible mass
Electrons participate in chemical reactions
Protons & neutrons participate in nuclear reactions
Atoms with the same atomic number but different atomic mass are called
__________
Same as atomic
number
Fill in the following table on isotopes.
Mass ― # of ptrotons
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Example: Determine the following for the element iron.
1. Atomic number?
2. Atomic mass?
3. Most common ion?
4. Number of electrons in atom?
5. Number of protons in atom?
6. Number of neutrons in most common isotope?
7. Number of valence electrons in least common ion?
*
Special Atoms:
Name 3 naturally diatomic elements:
Name 2 naturally polyatomic elements:
Sketching Diagrams of Atoms:
Remember that a nucleus consists of protons and neutrons that are held together by
binding forces.
Bohr and Rutherford’s models of an atom states that electrons are arranged in energy
levels (orbits) around the nucleus.
Bohr’s energy levels state that electrons are arranged as follows:
_____ max in first energy level
_____ max in second
_____ max in third
Electrons on outermost shell are called ________________________
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Bohr Atomic Diagrams:
Metal Atomic Diagrams:
Beryllium:
Sodium:
Written as: Be (
)
Na (
)
Non-Metal Atomic Diagrams:
Oxygen:
Chlorine:
Written as: O (
)
Cl (
)
Steps in Sketching Bohr Atomic Diagram:
1.
Bohr Atomic Diagram
2.
3.
–
–
–
–
–
–
–
–
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Group 1 has 1 valence electron (loses 1)
Group 2 has 2 valence electrons (loses 2)
Group 3 has 3 valence electrons (loses 3)
Group 4 has 4 valence electrons…pretty stable
*periodic table arrangement:
Group 5 has 5 valence electrons (gains 3)
atoms vs ions
Group 6 has 6 valence electrons (gains 2)
Group 7 has 7 valence electrons (gains 1)
Group 8 has full outer energy level (8 valence)…..very stable!!
• known as inert or noble gases
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Naming Ions:
 Positively charged elements (cations) are named with their full name and then
“_______”
 Negatively charged elements (anions) are named by dropping the suffix “ine”,
and adding “_________”
Fill in the following chart:
Polyatomic Ions:
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Topic 2 (Part A): Compounds
When two atoms come into close proximity of each other, their electrons are attracted to
both nuclei
•
What part of the atom participates in chemical reactions?
Compound Formation involves the sharing or transfer of valence electrons.
Sodium wants to
__________ its 1
valence electron to
become a complete
happy atom
Chlorine wants to
____________ 1
valence electron to
become a happy
atom
So… sodium gives away its 1 valence electron to chlorine and together they form a very
stable compound called __________ (table salt). This is a very happy union called an
______________ bond.
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Pure Substances (Elements) Bond to Form Compounds:
 Some atoms tend to transfer or share outer electrons (valence electrons) by
either trying to "give" them away or "take" them from other atoms.
What is a compound? (vs a molecule?)
Write the general formula for ionic and molecular compounds:
Ionic Compound
Molecular Compound
Type of
Compound
Elements
Electrons
(transfer or
sharing)
Conductivity?
Ionic
Molecular
In ionic compounds, which element loses electrons? Which gains electrons?
Atoms come together in various combinations to form molecules and compounds. Both
molecules and compounds are made of ___________________________
How do we know how many atoms there are?
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How many of each atom is there in the following:
Examples:
***When brackets are used the subscript applies to everything inside the bracket.
Examples:
Compound Coefficients: Coefficients appear ___________________ of a
formula to indicate how many there are.
What is the total number of atoms in “A” and “B” above?
Properties of Ionic Compounds (write down 3):



Ionic compounds that dissolve in water and conduct electricity as solutions are called
_____________________
Ionic compounds form 3-D grids called: ___________________.
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Writing Chemical Formulas (Ionic Compounds)
Don’t forget, you must balance the charges of each
element!!!
POSITIVES = NEGATIVES
Example 1: Write the chemical formula for barium fluoride.
Example 2: Write the chemical formula for calcium sulfide.
Example 3: Write the chemical formula for magnesium nitrite.
Example 4: Write the chemical formula for iron (III) oxide.
Homework:
1. Write the chemical formula for:
a. Hydrogen sulfide
_________________
b. Lithium nitride
_________________
c. Rubidium oxide
_________________
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2. Combine the following pairs of ions to form a neutral compound (Show all your
work).
(a)
Ca2+ Br-
_______________
(b)
Al3+ O2-
_______________
(c)
Zn2+ O2-
_______________
(d)
Na1+ N3-
_______________
(e)
Ba2+ S2-
_______________
(f)
Fe3+ Br-
_______________
(g)
Zn2+ N3-
_______________
(h)
K+
O2-
_______________
(i)
Pb4+ S2-
_______________
(j)
Al3+
N3-
_______________
(k)
Rb+
F-
_______________
(l)
Sn4+ Se2-
_______________
Answers:
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
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CaBr2
Al2O3
ZnO
Na3N
BaS
FeBr3
Zn3N2
K2O
PbS2
AlN
RbF
SnSe2
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Naming Ionic Compounds:
•
When naming ionic compounds, the metal name stays the same, the second
element (________________) always ends in “_______”
Name the following compounds:
• NaCl ____________________
•
H2S _____________________
•
Rb2O ____________________
•
Li3N _____________________
Homework:
Name the following compounds:
(a) Na2S(s)
_______________________
(b) Al2O3(s) _______________________
(c) AgCl(s)
_______________________
(d) MgBr2(s) _______________________
(e) BaCl2(s) _______________________
Naming Special Ionic Compounds:
Some ionic compounds are composed of a metal that can form more than one kind of
ion
• Ex. Copper has 2 ions Copper (I) Cu+ and Copper (II) Cu2+
Cu+
Cl-
=
CuCl
Copper (I) chloride
Cu2+
Cl-
=
CuCl2
Copper (II) chloride
Always look at the number after the non-metal!!!
Exercise:
Name the following compounds:
1. CrBr3
______________________________
2. Fe2O3
_______________________________
3. HgCl2
______________________________
4. NiO
______________________________
5. SbN
______________________________
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Write formulas for the following:
1. manganese II sulphide
____________________
2. iron III oxide
____________________
3. copper I chloride
____________________
4. cobalt III nitride
____________________
5. ruthenium III bromide
____________________
Naming Compounds with Polyatomic Ions:
Now try naming these compounds:
• NaHCO3 _________________
•
NaC6H5COO ______________
Example:
Al2(SO4)3
aluminum sulfate
Name the following:
l. Na2SO4 _______________________
7. CuCO3 _______________________
2. Ca(NO3)2______________________
8. H2CO3 ________________________
3. Fe3(PO4)2_____________________
9. MnSO4 _______________________
4. KClO3________________________
10. Hg(NO2)2_____________________
5. MnCrO4 _________________________
11. Al(OH)3 _____________________
6. K2SO4 _______________________
12. Al(NO)3_________________________
Going backwards!
Write the formula for the following compounds:
1. ammonium phosphate:
__________________
2. magnesium sulphate:
__________________
3. chromium chlorate:
__________________
4. sodium hydrogen carbonate __________________
5. potassium cyanide
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