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This internal is worth 6 credits.
This internal will cover 4 different reactions: Combination, Decomposition, Neutralisation, Combustion, Precipitation.
BASIC CHEMISTRY IDEAS - Atomic structure, Elements & Periodic table, ion formation
2.1 - Atom structure
2.1 - Atom structure
👀 Watch the video clip or go here
✍ Answer the questions below in your science book.
Name the 3 subatomic particles that make up an atom?
Where are neutrons found in an atom? What charge do they have?
Where are electrons arranged in an atom?
What is the symbol for Carbon? If Carbon has 6 protons, how many electrons does it have?
How many electrons does Helium have in its outer shell? Does this make it reactive or unreactive?
2.2 - Periodic table, Atomic Numbers & Masses
2.2 - Periodic table, Atomic Numbers & Masses
👀 Watch the video clip or go here periodic table
✍ Answer the questions below in your science book.
What is the atomic number of H, Mg, and Fe
What's the difference between mass and atomic numbers?
How are the elements organised in the periodic table in relation to mass and atomic numbers?
Choose a metal element and identify its symbol, atomic number, mass number, and how many electrons it has.
2.3 - Forming ions
2.3 - Forming ions
👀 Watch the video clip
✍ Answer the questions below in your science book.
What is an ion?
Copy & complete the sentences;
When an atom loses electrons they become ________________ charged and form ______________.
When an atom gains ____________ they become negatively ______________ and form ___________.
What is the outermost shell of electrons called?
How many electrons does sodium have in this shell?
When sodium reacts how many electrons does it lose?
How do we write the ion that is formed?
How many electrons does oxygen gain?
What ion does it form?
How do we write this ion?
Complete the challenge in the video - draw the calcium and chloride ions.
Challenge yourself - have you got it? Try some of the interactives and games here; https://phet.colorado.edu/sims/html/build-an-atom/latest/build-an-atom_en.html
Next steps in understanding how ions combine to form compounds -https://javalab.org/en/ion_model_en/ try this interactive to help visualise and understand numbers of ions in a compound.
👀 WATCH this about compounds: https://www.youtube.com/watch?app=desktop&v=RKSneJzwa7I
CHECK IN Q'S
Checking in on knowledge of Reactions, reactants and products, conservation of mass, Chemical equations, etc
Combustion Reactions:
Combustion Reactions:
An example of a combustion reaction - this is the one that takes place in the lab when we light our bunsen burners, depending on how much oxygen is available for the methane to burn will depend on what reaction takes place - Complete or incomplete combustion.
Complete Combustion - in excess of oxygen when fuels born the products are always the same
Incomplete Combustion - in a limited oxygen supply some of the products of combustion are different.
Burning Fuels - Complete combustion - When we burn fuels we can test for the products by using the following two tests;
> Cobalt chloride paper - turns from blue to pink when water is present
> Limewater - Limewater turns from clear to milky white when Carbon Dioxide is present.
The diagram below illustrates an example of this.
Combination Reactions:
Combination Reactions:
Definition: When two reactants combine to form one product.
General rule: A + B→ AB
Explaining the science:
A combination reaction occurs because there is a rearrangement of atoms.
One atom loses electrons to get a positive charge.
One atom gains electrons to get a negative charge
The positive charge is attracted to negative charge to form a new ionic compound.
Decomposition reaction:
Decomposition reaction:
Definition: When one substance breaks down to form two or more new substances.
General Rule: ABC→ AB+C
Explaining the science:
A reaction occurred because there was a rearrangement of atoms.
Heat is used to break the bonds of the larger compound into less complex compound.
This causes a small molecule to be released.
You can tell gas has been released due to the change in mass
Displacement Reaction:
Displacement Reaction:
Definition: When one more reactive metal swaps with a less reactive metal in a salt to make a new salt.
General Rule: A + CB→ AB + C
Explaining the science:
A reaction occurred because there was a rearrangement of atoms.
The more reactive metal solid will lose electrons and become a metal ion.
The less reactive metal ion will gain the electron(s) to become a metal atom.
We know what is more reactive due to the Reactivity series of metals, which you will be given.
Metal displacement reaction
The more reactive metal can displace the less reactive metal from its salt solution.
Exchange Reaction:
Exchange Reaction:
Definition: When two metal ions swap salts.
General Rule: AB + CD→ CB + AD
Explaining the science:
A reaction occurred because there was a rearrangement of atoms.
If one of the salts is insoluble (does not dissolve in water) a precipitate is formed.
A precipitate is a solid that is made from two liquids.
We know what is insoluble or soluble by following the six solubility rules, which you will be given.
Summing it up...
Summing it up...
What do you need to be able to do at the end of this learning... You will need to write a what you know about each of the 4 main reactions: Combination, Decomposition, Displacement and Exchange.
For each of these reactions you will need to cover:
Definition of the reaction
General Rule
Example word equation
Balanced symbol equation
Explain the scientific processes happening
Putting it in action
Putting it in action
CHECK IN Q'S
Checking in on knowledge of Reactions, reactants and products, conservation of mass, Chemical equations, etc
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