C3 – Unit 1

Started the new S3 Chemistry Course. This course is put together mainly concentrating on National 4 and 5 outcomes while incorporating the CFE experiences and outcomes for Level 4. It is a real mess.

Don’t worry, this Chemistry Course will be challenging and will be interesting.

You can change Educational theory but you can’t change Chemistry.

Lesson 1

Structure of the atom – looked at this website http://www.vtaide.com/png/atom.htm and answered the following questions

1. Sketch the diagram.

2. What are the names of the three particles found inside an atom?

3. What is the centre of the atom called

4. Which of the two particles are found there

5. What are the charges of each of these three particles.

6. Why are atoms electrically neutral?

7. How many protons does hydrogen have?

8. How many protons does nitrogen have?

9. How many neutrons does uranium-238 have?

The atom – it is the basic building block of chemistry which consists of electrons, protons and neutrons

At the center of the atom is the nucleus.

An atom has no charge as the number of protons and electrons are equal

Ion – an atom which has had electrons added or removed from it leaving it with an electrical charge.

Lesson 2

Definitions

Atomic number – number of protons in an atom’s nucleus

Mass number – number of protons plus neutrons in an atom’s nucleus

Nuclide Notation – shows all the information about the numbers of particles in an atom or an ion

 

 

So this is an ion of sodium

It has – 11 protons, 12 neutrons and 10 electrons

An ion is an atom which has lost or gained electrons.

Nuclide notation calculations


Lesson 3

Isotopes – internet research

1. Find a definition for an isotope

2. Find and list the stable isotopes for –

chlorine

magnesium

argon

bromine

See if the percentages that occur naturally can be found

Isotopes are atoms of the same element having the same Atomic number but different Mass numbers, ie. they differ in the number of neutrons.

Element Isotope Percentage
chlorine 35Cl 75.53
37Cl 24.47
magnesium 24Mg 78.70
25Mg 10.13
26Mg 11.17
argon 36Ar 0.34
38Ar 0.06
40Ar 99.60
bromine 79Br 50.54
81Br 49.46

Relative atomic mass

The relative atomic mass is the average mass of the isotopes of an element

For chlorine given above

    \[average = \frac{(75.53 \times 35) + (24.47 \times 37)}{100} = 35.49\]

As they are average values they are rarely whole numbers. They are given in atomic mass units.

Lesson 4

Electron arrangements

Electrons are arranged round the atom in shells or energy levels.

The first level can hold 2 electrons, the second 8 electrons and the third level up to 18 but usually 8 electrons.

Now work out electron arrangements for

Helium Boron Fluorine

Magnesium Phosphorus Argon

Lesson 5

History of the periodic table

Looked at this Powerpoint – periodic table history

Lesson 6

The Periodic Table – classifying – filling out small tables after research. The periodic table can be classified in different ways

Lesson 7

Periodic table film

Demonstrated reaction of sodium and potassium with water.

Here is potassium – a soft metal, stored in oil

Cut to expose a shiny surface

Reacts violently with water

And leaves behind an alkaline solution

Sodium is very similar though a bit less reactive.

They are alkali metals

Reaction of magnesium with oxygen (air)

Then dissolve the oxide formed in water

 

This slowly produces and alkaline solution

Magnesium is an alkali earth metal

 Lesson 8

The periodic table

Elements are arranged in the periodic table in order of increasing atomic number.

As far as Chemistry is concerned categorising as metals and non-metals is very important.

The stepped line to the right of the periodic table separates the metals and non-metals.

In the periodic table each row is called a period and each column is called a group.

Elements in the same group tend to have similar chemical properties. Some are given names –

group 1 – alkali metals

group 2 – alkaline earth metals

group 7 – halogens

group 8 or 0 – noble gases

The transition metals are in a block in the centre of the periodic table.

 

CFE Outcomes

Level 4

Through gaining an understanding of the structure of atoms and how they join, I can begin to connect the properties of substances with their possible structures.
SCN 4-15a

National 4

Atomic structure and bonding related to properties of materials
Basic atomic structure, including electron arrangement

A working knowledge of the structure of the periodic table, groups and periods is required for this Course.
All matter is made of atoms. When a substance contains only one kind of atom it is known as an element. Atoms contain protons, neutrons and electrons each with a specific charge, mass and position within the atom. The number of protons defines an element and is known as the atomic number. The mass number of an atom is the number of protons plus neutrons. Atoms do not have an electric charge and are said to be neutral.
Elements are arranged in the periodic table in order of increasing atomic number; elements with similar chemical properties are grouped together. Elements can be categorised as metals and non-metals.

National 5

Atomic structure and bonding related to properties of materials
Nuclide notation. Isotopes and relative atomic mass.

Learners should have knowledge of: sub-atomic particles, their charge, mass and position within the atom, the structure of the periodic table, groups, periods and atomic number. They should also be familiar with the seven diatomic elements.

When there is an imbalance in the number of positive protons and electrons the particle is known as an ion.
Chemists use nuclide notation to show the numbers of sub-atomic particles in an atom or ion.
Isotopes are atoms of the same element with different mass numbers. Relative atomic mass is the average mass of the isotopes present taking into account their relative proportions.