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1. Plaster of Paris in contact with moisture (water) changes to solid hard mass, gypsum. Therefore, it gets wasted. Hence it should be stored inmoisture proof containers.
2.Neutralization is a type of chemical reaction in which a strong acid and strong base react with each other to form water and salt.Bee stings are acidic in nature, which is why a household remedy for a bee sting is baking soda or sodium bicarbonate, which is a basic substance. A wasp sting, on the other hand, is mildly basic, so a household remedy for this will be vinegar, also known as acetic acid. These simple treatments ease these painful stings by a process called neutralization.
3.Uses of Washing Soda:
Sodium carbonate (washing soda) is used in glass, soap, and paper industries.
It is used in the manufacture of sodium compounds such as Borax.
Uses of Baking Soda:
Sodium hydrogen carbonate is also ingredient in antacids. ...
It is also used in soda-acid fire extinguishers.
4.By adding a very small amount ofbaking soda to fresh milk, themilkman keeps the milk unspoiled for little more time than usual time. As the pH value increases the milk turns to slightly alkaline, b) As baking soda is added, it turned into a base. But curd needs acidic condition to set.
5.Acids do not show acidic behaviour in the absence of water because the dissociation of hydrogen ions from anacid occurs in the presence of wateronly. It is the hydrogen ions that areresponsible for the acidic behaviour.
6.distilled water does not dissociate into ions. Since, conduction ofelectricity requires free ions so,distilled water does not conduct electricity. Rain water being an impure form of water, contains many ionic species. These ions are responsible for electrical conductivity of rain water.
2)The reaction between acid and base to form salt and water is called neutralisation reaction.
eg. NaOH+HCl---->NaCl+H2O
3)use of baking soda:it is used in manufacturing of baking powder and soda acid fire extinguisher .It is also used as antacid.
4)Because baking soda is alkaline and in summers milk get acidic resulting in sour taste.
5)Because acidic character is shown in the presence of hydronium ion which is formed by adding water to acid.
6)When rain water falls through atmosphere it dissolves acidic gases like CO2 and form acid H2CO3. Due to presence of the acid which breaks ti form ion rain water conduct electricity
7)sour substances contain bases which may react with the metal of the vessel to form poisonous metal compounds which may cause food poisoning .
8)Bleaching powder, Calcium oxychloride
9)Washing soda
10)When Baking soda is heated it produces Washing soda and water.
11). use:Bleaching powder is used as a disinfectant and oxidising agent in many industries.
property :Bleaching powder is a white crystal like substance.
12)Acids:HCl,acetic acid, methanoic acid
Base: NaOH,KOH
salt:NaCl, NH4Cl