Today's work: Chapter 3 - Compounds
Reading Check Pg 83 # 1 - 9
We practiced naming and writing some of the formulae on pages 86 - 91
Pg 95 # 1, 2abc, 3abcgh, 5abgh, 6abgh
Pg 97-99 (read only, just skim it).
Pg 106-107 Chapter 3 Review # 1 - 20 (#14 - 20 only do a +b for each question)
This weekend it is really important to study all your quizes and daily assignments as I am planning to give a Unit Test on Chapters #1-3 on Tuesday.
This is a good resource on different kinds of bonding and Van Der Waal Forces.
Chapter 2 Quiz Answers
1. C
2. B
3. C
4. B
5. C
6. D
7. C
8. A
9. D
10. A
11. F
12. G
13. B
14. H
15. D
16. A
PG 83 # 1 - 9
Checking Concepts
1. A chemical bond is a link between two atoms
that holds the atoms together.
2. Covalent and ionic
3. In a covalent bond, atoms are connected by
sharing a pair of electrons.
4. In an ionic compound, positive ions and nega-
tive ions are attracted to each other through
their opposite electric charges.
5. When a sodium atom loses an electron, it
becomes positively charged. When a chlorine
atom gains an electron, it becomes negatively
charged. All the negative charges repel each
other but attract the positive charges.
This results in an alternating arrangement
inside a crystal lattice.
6. (a) Lithium forms a positive ion, whereas fluo-
rine forms a negative ion.
(b) Li+and F–
7. (a) Two
(b) One
8. (a) Carbonate, CO
32–
(b) Phosphate, PO
43–
(c) Ammonium, (NH
4+) and nitrate, (NO3–)
9. (a) Covalent
(b) Four
(c) Polyatomic ion
PG 95 Checking Concepts
1. (a) Two
(b) The first part names the positive ion, while
the second part names the negative ion.
2. (a) Lithium, positive ion
(b) Nitrate, negative ion, polyatomic ion
(c) Iron(III), positive ion, multivalent metal
(d) Acetate, negative ion, polyatomic ion
(e) Chromium(II), positive ion, multivalent
metal
(f) Chloride, negative ion
(g) Perchlorate, negative ion, polyatomic ion
(h) Ammonium, negative ion, polyatomic ion
3. (a) Chromate, 1 chromium atom, 4 oxygen
atoms, 5 atoms in total, charge of 2–
(b) Dichromate, 2 chromium atoms, 7 oxygen
atoms, 9 atoms in total, charge of 2–
(c) Ammonium, 1 nitrogen atom, 4 hydrogen
atoms, 5 atoms in total, charge of 1+
(d) Acetate, 2 carbon atoms, 3 hydrogen
atoms, 2 oxygen atoms, 7 atoms in total,
charge of 1–
(e) Hydrogen sulphate, 1 hydrogen atom, 1
sulphur atom, 4 oxygen atoms, 6 atoms in
total, charge of 1–
(f) Sulphate, 1 sulphur atom, 4 oxygen atoms,
5 atoms in total, charge of 2–
(g) Sulphite, 1 sulphur atom, 3 oxygen atoms,
4 atoms in total, charge of 2–
(h) Sulphide, 1 sulphur atom, 1 atom in total,
charge of 2– (f) Mn
3P2
(g) Chromium(II) fluoride
(h) Copper(I) iodide
(i) Manganese(II) sulphide
(j) Lead(IV) oxide
(k) Tin(IV) oxide
(l) Chromium(II) nitride
6. (a) Magnesium hydroxide
(b) Potassium sulphate
(c) Aluminum hydrogen carbonate
(d) Copper(I) carbonate
(e) Iron(II) permanganate
(f) Ammonium sulphate
(g) Na 2SO4
(h) Ca 3(PO4)2
(i) Al(NO 3)3
(j) NH 4HSO4
(k) Pb(ClO3)4
(l) Fe2(CO3)3
PG 106 - 107
1. In an element, only one type of atom is pres-
ent. In a compound, atoms or ions from two
or more different elements are chemically
combined.
2. (a) Ionic and covalent
(b) In ionic compounds, one or more electrons
transfers between atoms, producing posi-
tive and negative ions. These ions are
attracted together because of their opposite
charges. In covalent compounds, two
atoms share the same pair of electrons, and
this sharing acts as a bond to hold them
together.
3. (a) Students’ drawings may vary but could
include either of the following:
Checking Concepts
1. In an element, only one type of atom is pres-
ent. In a compound, atoms or ions from two
or more different elements are chemically
combined.
2. (a) Ionic and covalent
(b) In ionic compounds, one or more electrons
transfers between atoms, producing posi-
tive and negative ions. These ions are
attracted together because of their opposite
charges. In covalent compounds, two
atoms share the same pair of electrons, and
this sharing acts as a bond to hold them
together.
3. (a) Students’ drawings may vary but could
include either of the following:
(b) The covalent bond is represented by the
“sticks” connecting the balls together or
the shared pair of electrons.
4. It is possible to keep dividing water by separat-
ing molecules until there is only one left. If a
molecule is broken up, this is a chemical
change and produces new substances with new
properties. This makes a single water molecule
the smallest possible sample of water.
5. Two neighbouring water molecules are not
covalently bonded. The covalent bonds exist
only between atoms of the same molecule.
6. All positive ions in an ionic lattice are
attracted to all other negative ions anywhere
in the lattice. However, the attraction
decreases with distance, and most of the
attraction is to the nearest negative ions.
7. (a) 2 chromium atoms and 7 oxygen atoms
(b) 2–
8. (a) Ionic
(b) Ionic
(c) Covalent
(d) Covalent
(e) Ionic
9. If the same chemical name applied to more
than one compound, this would lead to confu-
sion about which chemical is being referred to.
10. (a) International Union of Pure and Applied
Chemistry
(b) One important responsibility is to develop
rules for naming compounds.
11. (a) A reactant is a starting material in a chemi-
cal reaction. The reactant gets used up
during the reaction.
(b) A product is a material that is made during
a chemical reaction. The reactants turn
into products.
12. In an exothermic change, there is an overall
release of energy from the system. Often, this
means the reaction system warms up. In an
endothermic change, there is an overall
absorption of energy by the system as energy
flows into it.
Understanding Key Ideas
13. The carbonate ion CO
32–is like a molecule
because the carbon and three oxygen atoms
are covalently bonded to each other. It is like
an ion because the group of atoms carries an
electric charge of 2–.
14. (a) Sodium iodide
(b) Magnesium nitride
(c) Zinc oxide
(d) Aluminum fluoride
15. (a) Potassium nitride
(b) Calcium sulphide
(c) Silver sulphide
(d) Aluminum phosphide
(e) Strontium nitride
(f) Cesium oxide
16. (a) KBr
(b) K2O
(c) CaO
(d) Al2O3
(e) AlCl3
(f) Al2S
17. (a) Chromium(III) chloride
(b) Chromium(II) chloride
(c) Iron(II) chloride
(d) Iron(III) oxide
(e) Gold(I) oxide
(f) Gold(III) oxide
18. (a) FeF2
(b) FeF3
(c) CuF
(d) Cu2O
(e) CuO
(f) SnO2
19. (a) Ammonium phosphide
(b) Ammonium phosphite
(c) Ammonium phosphate
(d) Sodium phosphate
(e) Magnesium phosphate
(f) Iron(II) carbonate
20. (a) Na 2SO4
(b) Ca(NO3)2
(c) Al(OH)3
(d) Sr(HSO 4)2
(e) NH 4HSO4
(f) Ni(ClO )ionic compound
