1. Acids
A Guide to Common Fruit Acids
Most people probably know that citric acid is the source of a lemon’s sourness and acidity. However, it’s not the only acid found in fruits, or even in lemons. In fact, there are a whole range of different acids, with the particular ones present varying from fruit to fruit. This graphic takes a look at some of the main players and the fruits they’re found in.
Tutorial - Properties of Acids
In this video, we will discuss the physical and chemical properties of acids. At the end of this video, you should be able to
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Define an acid
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State the physical properties of acids
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State the chemical properties of acids
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Describe the test for hydrogen and carbon dioxide gases
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Write chemical and ionic equations
Tutorial - Strength and basicity of an acid
Strength and basicity of acids are commonly mixed up by students. Do you know the difference and are you able to classify them correctly?
How do strong and weak acids differ? Explore their effects on pH and electrical conductivity with this simulation!
2. Bases
Tutorial - Properties of Bases
In this video, we will discuss the physical and chemical properties of bases. At the end of this video, you should be able to
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Define a base and alkali and state their difference
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State the physical properties of bases/alkalis
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State the chemical properties of bases/alkalis
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Describe the test for ammonia gas
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Write chemical and ionic equations
Carbon Dioxide Extinguisher
Carbon dioxide is a gas that we interact with every day. For instance, carbon dioxide enables plants to perform photosynthesis, you exhale carbon dioxide when you breathe, and carbon dioxide can extinguish fire. You probably knew all those facts, but did you know that you can get really science-y and extremely creative when putting out flames with carbon dioxide? It's as simple as pouring the gas onto fire. Pouring? You better believe it!
3. The pH Scale
Tutorial - pH Scale and Oxides
This video introduces the pH scale and types of oxides.
At the end of this video, you should be able to
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Describe the relationship between pH and the concentration of hydrogen ions.
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State the colours of various indicators at different pH.
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Explain how soil pH can be controlled.
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Classify oxides into either acidic, basic, amphoteric or neutral.
pH Scale Infographic
The pH scale is something we’re all familiar with; most people will remember it from school chemistry lessons. It’s the scale used to rank how strong an acid (or alkali) a solution is. The colours associated with each number correspond to the colour that universal indicator turns in solutions of that particular pH. A fair proportion of people probably don’t know the chemistry behind the pH scale, though – where exactly do these numbers come from?
pH Scale Simulation
Test the pH of things like coffee, spit, and soap to determine whether each is acidic, basic, or neutral. Visualize the relative number of hydroxide ions and hydronium ions in solution. Switch between logarithmic and linear scales. Investigate whether changing the volume or diluting with water affects the pH. Or you can design your own liquid!
View in full screen
Click to download simulation
Red Cabbage Indicator
Ahh, the sweet smell of science! Invite your friends over to share in this super smelly but really cool activity. Plug your nose and get ready to make your own red cabbage indicator that will test the acidity or alkalinity of certain liquids.
4. Oxides
Oxide flashcards printable
An oxide is a compound formed when an element burns in oxygen. Are you having difficulties with the properties of various oxides?
Instructions:
Print the two pages ON SEPARATE SHEETS OF PAPERS and STICK THE TWO PIECES BACK-TO-BACK to make a your own flashcards! Please do this correctly otherwise everything will be wrong!
Note: Reaction of amphoteric oxides with bases are
not required in syllabus.
Dry Ice Bubbling Acid
Using acid-base chemistry and what you have learnt about oxides, how would you explain this cool demonstration?
