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Watch ACIDS BASES And SALTS with a new mindset to know that their balance in our body is the essence of our healthy living at https://www.google.com/<br><br>Acids, coming from the word u201cacereu201d,which are sour in taste & corrosive to touch.Bases which are bitter in taste & slippery/soapy to touch.<br>Solutions of substances that show different colour in acidic, basic or neutral solutions are called as Indicators.<br>Indicators may be natural obtained from plants(Lichen/Turmeric) OR may be artificial made from chemicals(Methyl orange,Phenolpthalein)<br>Substances that are neither acidic nor basic, are called neutral.<br>Acids and bases react with each other to neutralize and make Salts which may be acidic, basic or neutral in nature.<br>Different acid-base neutralizations from daily life have been taken up for explanation.<br>(Indigestion, soil pH, insect-bite, factory waste)<br><br>My Profile: https://www.slideserve.com/account/dashboard.php<br><br>More Slides:<br><br>https://bit.ly/2KUKpDf
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ACIDS,BASES AND SALTS(CLASS VII) By-Dr.Deepa Singh K.V.No.1 Armapur,Kanpur.
This presentation is about… • Acids, coming from the word “acere”,which are sour in taste & corrosive to touch. • Bases which are bitter in taste & slippery/soapy to touch . • Solutions of substances that show different colour in acidic, basic or neutral solutions are called as Indicators. • Indicators may be natural obtained from plants(Lichen/Turmeric) OR may be artificial made from chemicals(Methyl orange,Phenolpthalein) • Substances that are neither acidic nor basic, are called neutral . • Acids and bases react with each other to neutralize and make Salts which may be acidic, basic or neutral in nature. • Different acid-base neutralizations from daily life have been taken up for explanation.(Indigestion, soil pH, insect-bite, factory waste)
The learning objectives are based on 5E Plan: • 1.Students will be able to identify characteristics of Acids and Bases. • 2.Students will be able to understand the function of Indicators and differentiate between the natural and synthetic indicators. • 3.Students will be able to define and explain neutral behavior of Salts. • 4.Students will be able to explain the Neutralization reaction between an acid & a base. • 5.Students will be able to relate & explain different acid-base neutralization phenomena in our daily life.
SOURNATURAL ITEMS TO TASTE ARE BITTER DO YOU KNOW ME?
IF I AM SOUR TO TASTE & CORROSIVE TO SKIN? IF I AM BITTER TO TASTE & SLIPPERY TO SKIN? • My name is , • ACID , which is sour in taste . • Coming from Latin word “acere”, which means sour. • Acids are irritants(corrosive) to skin. • My name is , • BASE ,which is bitter in taste . • Bases are slippery or soapy to skin . Just to know me by sight/touch
But, any UNKNOWN acid or base cannot be tasted or touched by hand always, Then what to do ? • Special type of substances that are used to test ,whether a substance is an acid or a base, are calledIndicators. • These change their colour when added to an acidic/basic solution. • Indicators can be obtained fromnaturalsources or can be synthetic as chemicals. • Eg. China-rose/Rose, Red Cabbage,Turmeric,Litmus(natural) • Methyl Orange,Phenolpthalein,Universal Indicator(synthetic)
How to make paper –strip indicator from Turmeric or Rose • Make a solution of turmeric powder in a bowl. • Dip 5cm.long strips of filter paper/ cotton into the solution. • Drip it dry before use. • From a rose flower, pluck the petals. • Rub them on a 5cm.filter paper strip. • Allow the coloured-dye strip to dry before use.
To Use , & stripsPrepare 2 solutions in water,one with detergent/baking sodaanother with vinegar/lemon juice • 1.With turmeric,yellowcolour of the strip in detergent/baking soda changes toRED • 2.With vinegar/lemon juice,dull yellow colour changes to BRIGHT YELLOW. • 1.With rose,purplecolour of the strip with dtergent or baking soda changes to BLUE. • 2.With vinegar/lemon juice,purplecolour changes to PINK.
How to confirm this finding?By testing through a Standard indicator, which is called LITMUS, it is a blue dye obtained from Lichens sps. especially Rocellatinctoria. It changes colour fromblueto red at 4.5pH & red to blue at 8.5 pH .
Litmus Paper Test for confirmation • How to learn? • ANIL - • Acid>>Neela>>Laal • BELAN- • Base>> Laal>>Neela • (litmuscolour)
ENRICH YOUR KNOWLEDGE • NATURAL INDICATORS