1. Review the Atom
Label the Parts in notebook:
3.
1.
2.
4.

2. Review the Atom
Label the Parts in notebook:
3. Neutron
1. Nucleus
2. Electron
4. Proton

3. Elements and Compounds 2
Foundation Science 4 Class Code SC22102

4. Molecules
A molecule is 2 or more atoms connected to each other

5. Compounds
A compound is 2 or more DIFFERENT atoms connected
to each other

6. Practice
Answer molecules, compounds, or both in your foundation
notebook.
1.
2.
3.
4.
5.
6.
7.
8.

7. Answer Questions in Notebook
1.
2.
3.
4.
5.
A ________ is 2 or more atoms connected to each other.
A ________is 2 or more DIFFERENT atoms connected to each other
_________ is anything that has mass and takes up space.
An ________ is the basic unit of matter.
When something is made up of only one type of atom, it is called an
___________.
6. The ________ __________ is the number of protons in an atom.
7. Water (H2O) is a ______ (compound, molecule or both)
8. Nitrogen (N2) is a _______ (compound , molecule or both)

8. Answers
1.
2.
3.
4.
5.
A molecule is 2 or more atoms connected to each other.
A compound is 2 or more DIFFERENT atoms connected to each other
Matter is anything that has mass and takes up space.
An atom is the basic unit of matter.
When something is made up of only one type of atom, it is called an
element.
6. The atomic number is the number of protons in an atom.
7. Water (H2O) is a both (compound, molecule, both)
8. Nitrogen (N2) is a molecule (compound, molecule, both)

9. Elements in the Human Body
The human body is made up mostly of Oxygen (65%),
Carbon (18%) and Hydrogen (10%).
We are about 70%
water (= H and O)
The body also has:
3.2% Nitrogen
1.5% Calcium
1.0% Phosphorus

10. Elements in the Earth’s Crust
Earth’s crust is the outer layer…
Crust is:
50% Oxygen (O)
26% Silicon (Si)
7% Aluminum (Al)
4% Iron (Fe)

11. Atoms Like to Give or Share Electrons
This bonds them together
This creates a NEW substance called a molecule, with
new properties
Sodium (Na) metal is very dangerous
and explodes in water
Chlorine (Cl) is a very dangerous gas

12. Sodium (Na)

13. Atoms Like to Give or Share Electrons
This bonds them together
This creates a NEW substance called a molecule, with
new properties
Sodium (Na) metal is very dangerous
and explodes in water
+
Chlorine (Cl) is a very dangerous gas
But together, table salt
(NaCl) is completely
safe

14. Types of Chemical Bonds
Covalent Bond – atoms share outer electrons
Ionic Bond – electron moves from one atom to another

15. Examples of Ionic and Covalent Bonds
Water (H2O) is a covalent bond
Sodium chloride (NaCl) is an
ionic bond

16. Classification of Elements
Elements are classified into 3 states:
Solid
Silver
Liquid
Solid
Gas
Bromine
Liquid
Chlorine Gas

17. Chemical Formulas
The chemical formula shows what atoms and how many
are present in the compound.
Example…
H2O
Atomic symbols
How many hydrogen atoms present
If there is no number it means there is 1 atom

18. Chemical Formulas
Practice with using chemical formulas:
Alcohol C2H5OH
What atoms are present in this compound?
Carbon (C), Hydrogen (H) and Oxygen (O)
How many of each atom is present?
2 carbon atoms
6 Hydrogen atoms
1 oxygen atom

19. 1.
2.
3.
4.
5.
6.
7.
8.
Answer In Your Notebook
What is the most common element in the human body (by mass)?
What is the most common element in the earth’s crust (by mass)?
Is sodium metal (Na) a safe material?
Is chlorine gas (Cl) safe to breathe?
Is sodium chloride (NaCl) safe?
A ________ bond shares its electrons.
In a _________ bond electron(s) go from one atom to another.
How many atoms of each element are present in the compounds:
Refined sugar, C12H22O11
Sulphuric acid, H2SO4
Glucose, C6H12O6
Urea, CO (NH2)2
9. Which compound from above is this?
10. What is the chemical formula for
butane?