Acid Base
Que 1
What are acid base indicators?
Ans
Acid base indicators are mixture of dyes which are used to indicate the presence of acids and bases
Que 2
What are properties of acid
Ans
Acids are sour in taste
Acid change the colour of blue litmus to red
Whenever acids are dissolved in water they give H+ ion
Que 3
What are properties of a base
Ans
Bases are bitter in taste
Bases change the colour of litmus to blue
When bases dissolve in water they give hydroxyl ions (OH)-
Que 4
Name some natural indicators
Ans
Litmus and turmeric
Que 5
Name some synthetic indicators
Ans
Methyl orange and phenolphthalein
Que 6
What is litmus solution
Ans
Litmus solution is a purple dye which is extracted from the lesson it is commonly used as an indicator litmus solution is neither acidic or basic its colour is purple
Que 7
Name some acid base indicators
Ans
Hydrangea ,petunia, Geranium
Que 8
If we have three test tubes one of them contains distilled water other two contains acidic solution and basic solution and if we have a litmus paper how will be identify the contents
Ans
we draw all the solutions and all test tubes one by one on the litmus paper
The solution which has no effect on litmus paper shows that this test tube contain distilled water
The solution which turns red litmus paper to blue colour it shows that the solution is basic solution
And the solution in the test tube which turns litmus paper blue colour to red it shows that the solution is acidic solution
Que 9
What is indicator
Ans
Indicator tell us whether a substance is acidic or basic by changing its colour
Que 10
What are olfactory indicators
Ans
There are substances whose odour changes in acidic and basic media these are known as olfactory indicators for example Vanilla onion
Que 11
What is neutralisation reaction
Ans
Acid and base react with each other to form salt and water is known as neutralization reaction
Acid +Base= Salt+ Water
Que 12
What are alkali
Ans
Bases which are soluble in water are called alkali they are so be to touch bitter and corrosive
Que 13
What is universal indicator
Ans
Universal indicator is a mixture of several indicators it shows different colours at different concentrations of hydrogen ions in a solution
Que 14
What is pH scale
Ans
Scale for measuring hydrogen ion concentration in solution is called pH scale
on pH scale we can measure pH generally from 0 to 14
pH of a neutral solution is 7
PH less than 7 represents acidic solution
as the value of PH increases from 7 to 14 it represents increase in hydroxyl ion concentration in the solution presents basic solution
Que 15
What is brine solution
Ans
Aqueous solution of sodium chloride is called a brine solution
Que 16
Name the compound
a) used in soda acid fire extinguisher
Ans
Baking soda
b ) used to make drinking water free from germs
Ans
Bleaching powder
c) used to remove permanent hardness of water
Ans
Washing soda
d) used by doctors in treatment of fractured bones
Ans
Plaster of Paris
Que 17
What is the water of crystallization
Ans
What is the fixed number of water molecules present in one formula unit of a salt
Que 18
Name the acid which presence in the stomach of the human being
Ans
Hydrochloric acid
Que 19
PH value of element A is 5 and element Bis 12 which of them is acid and which of them is base
Ans
The elements which have PH value less than 7 are acidic in nature
The elements which have PH value greater than 7 and less than 14 are basic in nature
So element A is acid where as element B is base
Que 20
In order to make dilute acid why we not add water in acid
Ans
Acid are corrosive in nature so there must be a blast if we add water in acid so in order to make dilute acid we add acid in water drop voice drop
Sat Dec 3, 2022