Before this new topic, let´s
check our knowledge:
Workbook: 60-61-62-63
COMPOUNDS
https://www.brainpop.com/science/matterandchemistry/compoundsandmixt
ures/
Let´s read together page
86 COURSEBOOK
Answer this in your notebook
Describe Two ways in which sodium chloride
is different from sodium.
Describe Two ways in which sodium chloride
is different from chlorine
NAMING COMPOUNDS
First the metal name.
Non metal name is changed: sodium chlorine
 sodium chloride.
Ending: ide
LET´s PRACTICE (in pairs)
Workbook Page 64: exercises 1 and 2.
CHALLENGE
 Complete by yourself exercise 7.5 from page 65 (Workbook)
Next class:
 PPT presentation (Science fair Project)
Elements and Compunds
Exercise 7.1 Atoms
 1 A and C.
 2 All the atoms in an element are of just one type.
 3 Atoms are single particles, whereas molecules are made up of at least
two atoms bonded together.
 4
•
The first box should contain six individual circles, not touching one another.
•
The second box should contain four pairs of circles. In each pair, the two
circles should be touching, but there should be space between the four
pairs.
•
The third box should contain three pairs of circles (as in the second box),
plus two groups of four circles.
•
The circles in the groups of four should be touching one another, but there
should be no contact between the groups and pairs.
The Periodic Table
Workbook pg 61 & 63
 Exercise 7.3 The Periodic Table
 1)
• a false
• b true
• c true
• d true
• e false
• f true
 2 )The following should be circled: chlorine, carbon, sulfur, neon and
helium.
 3 Name of element Symbol of element
calcium
Ca
Carbon
C
Oxygen
O
beryllium
Be
hydrogen H
potassium K
neon
Ne
Chlorine
Cl
4 The symbol for sodium is Na because it comes from the old Latin for
sodium which is natrium.
Topic 7.4 Compounds
 1 Any two from: sodium chloride does not react with water but
sodium does; sodium chloride does not have a shiny surface like the
cut surface of sodium; solid sodium chloride does not conduct
electricity but solid sodium does; sodium chloride is white whereas
sodium is a silver colour; you can eat sodium chloride but you
cannot eat sodium.
 2 Any two from: sodium chloride is a solid whereas chlorine is a gas;
chlorine is poisonous while sodium chloride is not and you can eat it;
chlorine is greenish in colour whereas sodium chloride is white.
Exercise 7.4 Compounds
 1 .• a iron chloride
• b sodium oxide
• c calcium carbonate
• d hydrogen fluoride
• e potassium nitrate
• f potassium nitride
8 2 Unit 7.2
• a magnesium and oxygen
• b carbon and oxygen
• c copper, sulfur and oxygen
• d calcium, chlorine and oxygen
• e aluminium and chlorine
• f sodium and sulfur
Exercise 7.5 Using formulae
 1 potassium, hydrogen and oxygen
 2 hydrogen and oxygen
 3 a hydrogen, sulfur and oxygen b two atoms of hydrogen, one atom of
sulfur and four atoms of oxygen
 4 Chemical
Formula What
the compound
contains:
Chemical
Namename
Formula
What
the Compounds
contain

magnesium oxide
MgO
one magnesium atom bonded to one oxygen
atom sulfur dioxide
SO2
one sulfur atom bonded to two oxygen atoms
aluminium chloride
AlCl3
one aluminium atom bonded to three
MgCO3
one magnesium atom bonded to one carbon
atom and three oxygen atoms
atom magnesium
carbonate