C8 Acids, Bases and Salts

Vocabulary

https://quizlet.com/_929rdr?x=1qqt&i=28b19k

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• The pH scale is a numerical scale which is used to show how acidic or alkaline a solution is
• It goes from 1 - 14 (extremely acidic substances can have values of below 1)
• All acids have pH values of below 7, all alkalis have pH values of above 7
• The lower the pH then the more acidic the solution is
• The higher the pH then the more alkaline the solution is
• A solution with a pH of 7, such as water, is described as being neutral

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C8 Acids, Bases and Salts

What is the pH scale?

C8.1.1 Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using Universal Indicator

C8 Acids, Bases and Salts

C8.1.1 Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using Universal Indicator

C8 Acids, Bases and Salts

C8.1.1 Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using Universal Indicator

1. Match the acid with its formula.

2. Match the alkali with its formula.

3. Can you name some everyday acids and alkalis?

Investigating Indicators

Complete the task below

C8.1.1 Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using Universal Indicator

C8 Acids, Bases and Salts

How do you name salts?

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

copper oxide

hydrochloric acid

copper chloride

zinc oxide

hydrochloric acid

zinc chloride

magnesium oxide

sulphuric acid

magnesium sulphate

magnesium oxide

nitric acid

magnesium nitrate

Acids and Alkalis (Bases)

What is an acid?

C8.1.1 Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using Universal Indicator

• Acids have pH values of below 7, have a sour taste (when edible) and are corrosive
• In acidic conditions blue litmus paper and universal indicator turns red
• Acids are substances that can neutralise a base, forming a salt and water
• The presence of H⁺ ions is what makes a solution acidic

• Bases have pH values of above 7
• A base which is water-soluble is referred to as an alkali
• In basic (alkaline) conditions red litmus paper and universal indicator turns blue 
• Bases are usually oxides or hydroxides of metals
• The presence of the OH^- ions is what makes the aqueous solution an alkali

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Acids and Alkalis (Bases)

What is an acid?

C8.1.1 Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using Universal Indicator

C8 Acids, Bases and Salts

C8.1.1 Describe neutrality and relative acidity and alkalinity in terms of pH (whole numbers only) measured using Universal Indicator

Alkalis

Acids

Strong

Weak

Weak

Strong

Neutral

C

B

A

*

Magnesium chloride

Lead nitrate

Zinc nitrate

Copper sulphate

Iron nitrate

Zinc sulphate

Lead chloride

Copper sulphate

Chromium nitrate

Tin sulphate

Iron sulphate

Ammonium chloride

C8 Acids, Bases and Salts

How do you name salts?

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

Acid    +    Base   →    Salt    +    Water

C8 Acids, Bases and Salts

Acids and Bases

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

Hydrochloric Acid    +    Sodium Hydroxide  →    Salt    +    Water

Sulphuric Acid    +    Sodium Hydroxide  →    Salt    +    Water

Acids and Metals

Write an equation for the following sentence

Task 1:

Magnesium reacts with hydrochloric acid

magnesium + hydrochloric acid → magnesium chloride + hydrogen

Mg + 2HCl → MgCl₂ + H₂

Support: metal + acid → salt + hydrogen

Challenge: Write a chemical equation for the reaction

to produce magnesium chloride + hydrogen

Acids and Metals

Write an equation for the following sentence

Task 1:

Lithium reacts with sulphuric acid to produce lithium sulphate and hydrogen

lithium + sulphuric acid → lithium sulphate + hydrogen

Li + H₂SO₄ → Li₂SO₄ + H₂

Support: metal + acid → salt + hydrogen

Challenge: Write a chemical equation for the reaction

Acids and Metals

Write an equation for the following sentence

Task 1:

Potassium reacts with nitric acid to produce potassium nitrate and hydrogen

potassium + nitric acid → potassium nitrate + hydrogen

K + HNO₃ → KNO₃ + H₂

Support: metal + acid → salt + hydrogen

Challenge: Write an unbalanced chemical equation for the reaction

Neutralisation

What is the equation for neutralization?

Starter

Challenge: Create the most neutral solution

Neutralisation

All of the traffic lights have gone out in Vietnam!!

Starter

Challenge: Can you create traffic light using chemicals?

You have:

Universal Indicator

HCL

NaOH

Water

Conical Flask

• Today I saved Vietnam by…
• Firstly, I mixed… to make
• Secondly, I mixed
• Lastly, I mixed
• The hardest colour to make was…
• I did this by…

Neutralisation

Reflection.

Starter

Acid    +    Metal   →    Salt    +    Hydrogen

C8 Acids, Bases and Salts

Acids and Metals

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

Hydrochloric Acid + Magnesium 🡪 Magnesium Chloride + Hydrogen

Sulphuric Acid + Magnesium 🡪 Magnesium Sulphate + Hydrogen

Pop Test for Hydrogen Gas

Why do bath bombs fizz?

C8 Acids, Bases and Salts

Acids and Carbonates

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

• A luxury soap manufacturer would like to produce a new, extremely fizzy, bath bomb.
• The fizzier it is, the quicker it will dissolve and release its fragrance.
• You have been asked to find out which metal carbonate makes the best bath bombs.
• You will be provided with a basic method for making the bath bombs.

C8 Acids, Bases and Salts

Acids and Carbonates

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

• HCl + CaCO₃ 🡪 CaCl₂ + H₂O + CO₂

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1. Which chemical formula represents the calcium carbonate?
2. Which chemical formula represents carbon dioxide?
3. What are the formulas for the other products of the reaction? Do you know the names of these products?
4. Why is this important to know the products of a reaction when making bath bombs?

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C8 Acids, Bases and Salts

Acids and Carbonates

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

C8 Acids, Bases and Salts

Acids and Carbonates

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

1. Weigh out the dry ingredients (citric acid, bicarbonate of soda and cornflour) using a balance.
2. Mix the dry ingredients well in a plastic beaker using a spatula or a spoon. Take care to get out any lumps.
3. Measure out 5cm of sunflower oil in a measuring cylinder using a funnel to avoid spillage.
4. Add the oil to the dry ingredients a bit at a time, stirring well all the time.

C8 Acids, Bases and Salts

Acids and Carbonates

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

• 5. When it has all been incorporated, mould the mixture with your hands, into a ball. You will have to squeeze pretty hard and it will make a mess! Do it over newspaper or a paper towel. If the mixture does not hold together then return to the plastic beaker and stir in a little more sunflower oil and try again

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C8 Acids, Bases and Salts

Acids and Carbonates

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

Acid  +  Metal Carbonate → Salt  +  Carbon Dioxide  +  Water

C8 Acids, Bases and Salts

Acids and Carbonates

C8.1.2 Describe the characteristic properties of acids (exemplified by dilute hydrochloric acid and dilute sulfuric acid) including their effect on litmus paper and their reactions with metals, bases and carbonates

Hydrochloric Acid  +  Sodium Carbonate → Salt  +  Carbon Dioxide  +  Water

Citric Acid  +  Sodium Carbonate → Salt  +  Carbon Dioxide  +  Water

• Soil pH is analysed to indicate the acidity or alkalinity of soil
• Most plants favour a pH value of between 5 and 8
• Changes in soil which cause a pH to be outside this range adversely affect plant processes resulting in reduced growth and crop yield
• Soils may become acid from acid rain, overuse of fertilisers which contain ammonium salts or by the excessive breakdown of organic matter by bacteria
• Crushed or powdered limestone (calcium carbonate) or lime (calcium oxide) or slaked lime (calcium hydroxide) is added to neutralise the excess acidity in the soil

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C8 Acids, Bases and Salts

Why is the soil acidity important?

C8.1.3 Describe and explain the importance of controlling acidity in soil

C8 Acids, Bases and Salts

What is an indicator?

Practical

C8 Acids, Bases and Salts

What other food sources can be used as an indicator?

Task 1:

Challenge: Explain why food sources can act as an indicator

Number 1: Collect Red Cabbage, Filter paper and Funnel

C8 Acids, Bases and Salts

Make an indicator

Task 2:

Challenge: what equipment do you require for this experiment?

Number 3: Collect Bunsen burner, heat proof mate, gauze, tripod 🡪 Setup and check gas

Number 2: Collect 3 beakers and fill one with approximately 50ml of water

Number 1: Collect spotting tile and 4 pipettes

Number 3: Collect Bunsen burner, heat proof mate, gauze, tripod 🡪 Setup and check gas

Number 2: Collect

Making your own indicator

1. Cover the red cabbage with boiling water
2. Wait for 5 minutes (get your results table ready in this time)
3. Filter the liquid into a fresh beaker

Testing the pH

1. Place a few drops of the substance into 2 dimples of the spotting tile
2. Add the universal indicator to one and the red cabbage indicator to the other
3. Record the results

C8 Acids, Bases and Salts

Making your own indicator

Starter

C8 Acids, Bases and Salts

What is an indicator?

Starter

Challenge: Can you make your own pH scale by adding acids and alkalis to your indicator

Use the litmus paper to test the unknown substances

C8 Acids, Bases and Salts

Does an indicator need to be a solution?

Task 2:

Challenge: suggest advantages disadvantages of using a solution

What was the disadvantage?

What is the alternative?

C8 Acids, Bases and Salts

Match the solution with a pH

Starter

Challenge: Suggest a solution to add to the chart

Decide where on the pH scale to place…

• lemon juice
• bleach
• pure water
• stomach acid
• Pancreatic juice
• fizzy drinks
• drain cleaner
• acid rain

C8 Acids, Bases and Salts

Complete the worksheet

Task 1:

Challenge: Write the chemical equation for each

C8 Acids, Bases and Salts

Correct the worksheet

Task 1:

Copper + Sulphuric Acid > Copper Sulphate + Hydrogen

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Calcium + Nitric Acid > Calcium Nitrate + hydrogen

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Potassium + Sulphuric Acid > Potassium Sulphate + Hydrogen

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Copper + Hydrochloric Acid > Copper Chloride + Hydrogen

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Magnesium + Sulphuric Acid > Magnesium Sulphate + Hydrogen

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C8 Acids and Bases

Complete the following

Checkpoint

1.

2.

3.

4.

5.

C8 Acids, Bases and Salts

Discuss the properties of an iron nail

Starter

Challenge: What are iron nails used for? Why?

This is an Iron (Fe) Nail

What are my properties?

Challenge: What are some other uses for iron?

C8 Acids, Bases and Salts

Find a solution to how this occurred

Task 1

• Oxidation is the reaction in which a substance combines with oxygen. Metals react with oxygen in the air to produce metal oxides. For example, magnesium reacts with oxygen to produce magnesium oxide when it is heated in air:

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Metal + Oxygen 🡪 Metal Oxide

magnesium + oxygen → magnesium oxide

2Mg + O₂ → 2MgO

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C8 Acids, Bases and Salts

Copy and Complete.

Task 2

1.

2.

3.

https://forms.office.com/Pages/ResponsePage.aspx?id=KheSDBwaEUybg3pLxZlckfCWKUWRx4FArTzFC0TbyRFUQVpET05SVEFTVTgyWko0NEJKNE5YNTRCRS4u

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C8 Acids and Bases

Complete the following

Checkpoint

C8 Acids and Bases

Kahoot

Checkpoint