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Acids, Bases and Salts

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Introduction

Acids tend to have a _ _ _ _ taste (vinegar for e.g contains _ _ _ _ _ _ _ _ acid and _ _ _ _ _ juice contains citric acid)

Many Alkalis have a soapy/slippery feel. When alkalis do NOT dissolve in water they are called _ _ _ _ _.

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How strong??? Acids have a pH _ _ _ _ than 7. The _ _ _

_ _ _ _ _ the acid the _ _ _ _ _ the pH number.

_ _ _ _ _ _ _ _ solutions have a pH of more than 7. The stronger the alkaline the _ _ _ _ _ _ the pH number.

pH scale

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Acids An acid is a compound

containing hydrogen which become H+ _ _ _ _ in _ _ _ _ _.

Acids turn _ _ _ _ litmus paper _ _ _.

They turn universal indicator _ _ _ if they are strong, and orange and yellow if they are _ _ _ _.

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Examples of acidsNAME FORMULA pH FOUND IN

Sulphuric acid H2SO4 1 _______________

_ _ _ _ _ _ acid C6H8O7 Weak acid

Lemons, oranges

Ethanoic acid _______ 4 Vinegar

_ _ _ _ _ _ acid HNO3 1 Used in __________

(clue: plants) and

explosives

Carbonic acid H2CO3 4 _________

Hydrochloric acid

____ ___ Stomach

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Alkalis Alkalis turn _ _ _ litmus paper _ _

_ _. They turn _ _ _ _ _ _ _ _ _

indicator dark blue or purple if they are _ _ _ _ _.

Alkalis are a type of BASE: ones that _ _ _ _ _ _ _ _ in water. They _ _ _ _ _ _ _ _ _ _ acids.

They release ___- ions in water

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Examples of Bases and AlkalisNAME FORMULA DISSOLVE

IN H2O?ALKALI

OR BASE?FOUND IN

__________________

CuO No _______ -

Sodium hydroxide

_______ _____Alkali Used to

remove grease from

ovens + used to make _ _ _

_

___________ NH3 Yes ________Main active ingredient in

household _ _ _ _ _ _ _ _

fluids

_____________________

Ca(OH)2 ___ Base Slaked lime used in

agriculture

Aluminium hydroxide

Al(OH)3 ____ Base Used in some _____________ tablets

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Neutral substances

_ _ _ _ _ is a neutral substance

It turns universal indicator paper green

No effect on _ _ _ _ _ _ paper It has a pH of exactly __

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Neutralisation The making of _ _ _ _ _!

+

This reaction is called neutralisationneutralisation.

The alkali has neutralised the _ _ _ _ by removing its H+ ions, and turning them into _ _ _ _ _.

H2O(l)

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Uses of Neutralization:

Indigestion tablets: weak _ _ _ _ in these will react with ___________ acid in your stomach….so go easy on the Steers!!

• Soil treatment-farming: _ _ _ _ _ _ soil is treated with a BASE…why not alkali?

• Insect stings: - _ _ _ stings are acidic…so can be treated with a base (calamine lotion-zinc carbonate). Wasp stings are _ _ _ _ _ _ _ _ hence an acid (vinegar-ethanoic acid) can be used.

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Different methods of salt production

Method 1 : Acid + metal _ _ _ _ _

Method 2 :

Acid + metal carbonate

Method 3:

Acid + _ _ _ _ _ _

Salt + water

Salt + water + ____

Salt + water

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What you need to remember!!

Properties and examples of acids (weak and strong)

Properties and examples of alkalis and bases (weak and strong)

Preparation, separation and purification of of neutral substances (soluble salts and insoluble salts)

pH scale and other indicators

Reactions of making of salts

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Thankyou for listening!!

Good luck for the test.