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Year 8

Every been stung by a bee?

Next time add some tooth paste to it.

Neutralisation

Every been bitten by a Mosquito?

Next time wash the bite with mild soap.


Every been stung by a Box jelly fish?

Next time wash the infected area with some vinegar


Every been stung by a wasp?

Next time place some lemon juice or vinegar over the sting



So, what do all these things have in common?

Some of these are acids while others are alkali
What you should notice is that all the acids are paired up with an alkali.

When you neutralise a strong acid you try to bring it back to a neutral pH. So you add an alkali.

When you have a strong alkali you neutralise it by adding an acid to it, to bring it back to neutral pH.

What substance neutralise acids?

Something which can neutralise an acid is called a Base.

Sodium hydroxide, calcium oxide and copper oxide are examples of bases.

If it is soluble (dissolves in water) then it is considered an alkali.

We can use neutralisation in farming. Some soils around the world are slightly more acidic.
Every plant however has a favourite pH to grow in. So in order to grow a specific plant you need to make the soil the correct pH.

Some tea plants require a pH of 5.5, apple trees 6, cabbage 6.5 and tomatoes 6.

If the soil is too acidic, you can add base to the soil to make it less acidic.

Have you ever heard of acid rain?

In reality, acid rain is very weak, it won’t burn your cloths of, but it can cause serious affects to the ecosystem.

How is it formed?

Burning coal can create sulfur dioxide gas (acidic gas). This gas dissolves in rainwater, creating acid rain.

As the rain falls, it makes lakes and the soil more acidic. This makes it hard for animals and plants to live in these environments.

In order to fix this, environmental organisations add bases to acid lakes. The pH of the lakes increase, making them closer to neutral.


Questions

1. Research what to do if you are bitten by the following insects. State if their bite is acidic or alkaline.

    - Fire ant

    - Hornets

    - Carabid beetles

    - Box jelly fish

    - Sea urchins


2. Define what is meant by Neutralisation?


3. Old McDonald had a farm, and on that farm he has soil which had a pH of 7.0.               a. Research 3 crops which he should try growing.

         b. McDonald wants to grow bananas in his farm. Should he add an acid or              base to the soil to grow bananas?

4 .While trying to alter the pH of the soil Old McDonald accidentally used to much acid, turn the pH from 7.0 to 3.0.

         a. What would McDonald need to do to his soil to grow Coconuts?

         b. Give 1 example of something that can grow in pH of roughly 4.5


5. Define what an alkali is?


6. Why can’t water in the ocean ever be 100% neutral?


7. You have a lot of acid reflux or stomach digestion issues, what should you take and explain why?


8. Explain how acid rain is created, how it affects the ecosystem and how we can fix it.