Acid bases and salts 17 jul 13

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PRESENTATION ON PRESENTATION ON ACIDS, BASES AND SALTSACIDS, BASES AND SALTS

BYBYN SAI DEEPIKAN SAI DEEPIKA

& & N SAI DEEPAKN SAI DEEPAK

ACIDSACIDS AcidsAcids are those substances which are sour are those substances which are sour in in

taste, produce burning sensation on taste, produce burning sensation on touching and touching and which turn blue litmus to red. which turn blue litmus to red. Examples – Citric acid, Examples – Citric acid, oxalic acid, oxalic acid, hydrochloric acid.hydrochloric acid.

Curd, lemon juice, orange juice and vinegar Curd, lemon juice, orange juice and vinegar taste sour. These substances taste sour taste sour. These substances taste sour because because they contain acids.they contain acids.

The chemical nature of such substances is a The chemical nature of such substances is a acidicacidic. The word acid comes from the Latin . The word acid comes from the Latin word word acere acere which means sour.which means sour.

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ACIDS

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NAME OF ACID FOUND IN

Acetic Acid Vinegar

Formic acid Ant’s sting

Citric Acid Citrus foods such as oranges, lemons etc

Lactic Acid Curd

Oxalic Acid Spinach

Ascorbic Acid (Vit ‘C’) Amla, citrus fuits

Tartaric Acid Tamarid, grapes, unripe mango etc

BASESBASES

Bases are those substances which are Bases are those substances which are bitter bitter in taste, are soapy to touch and in taste, are soapy to touch and which turn which turn red litmus to blue. Example red litmus to blue. Example Sodium Sodium Hydroxide, Potassium hydroxide etc.Hydroxide, Potassium hydroxide etc.

The nature of such substances is said to The nature of such substances is said to be be basic.basic.

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BASES WE EAT

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NAME OF BASES FOUND IN

Calcium Hydroxide Lime Water

Ammonium Hydroxide

Window Cleaner

Sodium Hydroxide/Potassium Hydroxide

Soap

Magnesium Hydroxide

Milk of Magnesia

INDICATORSINDICATORS

The special substances which are used to The special substances which are used to test whether a substance is acidic or basic test whether a substance is acidic or basic are known as indicatorsare known as indicators

The indicators change colour when added The indicators change colour when added to to a solution containing an acidic or a basic a solution containing an acidic or a basic

substance.substance. Some of the naturally occurring indicators Some of the naturally occurring indicators

are are turmeric, litmus, china rose petals turmeric, litmus, china rose petals etc.etc.

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LITMUS PAPER

NEUTRALISATIONNEUTRALISATION

The reaction between an acid and a base The reaction between an acid and a base is is known as neutralization. Salt and water known as neutralization. Salt and water are are produced in this process with the evolution produced in this process with the evolution

of heat. of heat. In neutralization reaction heat is always In neutralization reaction heat is always

produced or evolved.produced or evolved. In neutralization reaction a new substance In neutralization reaction a new substance

is formed. This is called salt. Salt may be is formed. This is called salt. Salt may be acidic, basic or neutral in nature.acidic, basic or neutral in nature.

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ACTIVITY TEST WITH DIFFERENT ACTIVITY TEST WITH DIFFERENT INDICATORSINDICATORS

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TEST SOLUTION CHINA ROSE INDICATOR

TURMERIC INDICATOR

LITMUS SOLUTION BLUE/RED

HCL (Hydrochloric Acid)

Red No change Blue to Red

NAoH Sodium Hydroxide

Green Red Red to Blue

Soap solution Green Red Red to Blue

Baking Powder Green Red Red to Blue

Lemon Juice/ Tomato Juice

Red No Change Blue to Red

Vinegar Red No Change Blue to Red

Sugar No Change No Change No Change

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