Question 1 :
Phenolphthalein gives a pink colour in alkalinate medium due to the fact that:

Question 2 :
The substances which give different colours with acid and base are called __________ .

Question 4 :
Which of the following shows differential coloring in acidic and basic solutions?

Question 6 :
Indicator is a substance which shows different colors in acidic and basic solutions.

Question 9 :
Which of the following exhibits different colors in acidic and basic solutions?

Question 11 :
In the titration of ferrous ammonium sulphate and potassium dichromate, the external indicator used is:

Question 14 :
One drop of methyl orange solution when added to the solution obtained after electrolysis of a concentrated solution of NaCl with Pt electrodes, the colour of the solution will turn:

Question 15 :
When phenolphthalein is added to $NaOH$ solution, the colour changes to:

Question 16 :
Which of the following solutions will resist change in pH upon addition of small quantity of water?<br/>

Question 18 :
When phenolphthalein is added to $NaOH$, the colour of the solution will become __________.

Question 20 :
<table class="table table-bordered"><tbody><tr><td>&#160;Indicator</td><td>&#160;pH range</td></tr><tr><td>&#160;Methyl violet</td><td>&#160;0.3-1.8</td></tr><tr><td>&#160;Methyl orange</td><td>&#160;2.8-3.8</td></tr><tr><td>&#160;Congo red</td><td>&#160;2.8-4.8</td></tr><tr><td>&#160;Methyl red</td><td>&#160;3.8-6.1</td></tr><tr><td>&#160;Bromothylmol blue</td><td>&#160;6.0-7.9</td></tr><tr><td>&#160;Phenol Red</td><td>&#160;6.8-8.6</td></tr></tbody></table>The table above shows the pH ranges of some common indicators. Given that $K_{a}$&#160; is $7.3 \times 10^{-10}$ for boric acid $(H_{3}BO_{3})$, Choose an indicator that can be used for the titration of $0.10 M KH_{2}BO_{3}$ with 0.10 M HCl.<br/>

Question 21 :
Which acid is used in dentistry and orthodontics as an etching solution?

Question 22 :
To protect tooth decay we are advised to brush our teeth regularly. The nature of the toothpaste commonly used is:

Question 28 :
Which is false for the following reaction?<br>$\underset { A }{ { \left[ Cu{ \left( { H }_{ 2 }O \right) }_{ 3 }OH \right] }^{ + } } +\underset { B }{ { \left[ Al{ \left( { H }_{ 2 }O \right) }_{ 6 } \right] }^{ 3+ } } \longrightarrow \underset { C }{ { \left[ Cu{ \left( { H }_{ 2 }O \right) }_{ 4 } \right] }^{ 2+ } } +\underset { D }{ { \left[ Al{ \left( { H }_{ 2 }O \right) }_{ 5 }OH \right] }^{ 2+ } } $

Question 34 :
Remedies of which of the following are examples of neutralisation in everyday life?<br/>

Question 37 :
Which indicator is correctly paired up with its proper colour if it were added to a base?&#160; <br/>i. Litmus - blue&#160;<br/>ii. Phenolphthalein - pink <br/>iii. Methyl orange - yellow

Question 39 :
What volume of $ 0.18 N - KMnO_{4} $ solution would be needed for complete reaction with 25 ml of $ 0.21 N - KNO_{2} $ in acidic medium ?

Question 40 :
Which of the following base is used for cleaning and commonly known as lye?

Question 45 :
Which acids/ bases are used for the following?<br/>(i)&#160;To neutralize sting of wasps<br/>(ii) In alkaline batteries<br/>(iii) Manufacturing of soap

Question 46 :
A blue litmus paper was first dipped in dilute $HCl$ and then in dilute $NaOH$ solution. It was observed that the colour of the litmus paper ___________.<br/>

Question 47 :
Which of the following base is used as antacid to neutralize stomach acidity?

Question 48 :
An example of a solution which is not in equilibrium is&#160;:<br/>

Question 50 :
Which of the following is used as preservative and flavoring agent?

Question 51 :
The acidic behavior of lakes and oceans can be neutralized by:

Question 52 :
Whatis mixed with sand and water to make mortar which is used in the construction of buildings?

Question 53 :
Which one of the following types of medicines is for treating indigestion ?

Question 55 :
If the soil is basic the plant do not grow proper, what should we add to it to improve its quality?

Question 56 :
What parameter does an indicator changes, with change in the nature of the solution?

Question 60 :
Which solution is a conjugate acid/base pair with differing spectral absorbencies?&#160;<br/>

Question 61 :
Lalita has taken sulphur powder $(P)$ in a deflagrating spoon, burnt it and put it in a gas jar. Then she removed the spoon and added water. In another experiment, she has taken water in one beaker and added a small piece of sodium $(Q)$. After some time, she took both the solutions and checked them with litmus paper.&#160;What result would she expect?

Question 63 :
In the titration of $K_{2}Cr_{2}O_{7}$ iodometrically, near the end point the colour of the solution becomes:

Question 65 :
Which of the following indicator is the best indicator for the detection of end point in the titration of $CH_3COOH$ and $KOH$?

Question 67 :
An organic dye, cosin used to detect end point of precipitation titration by adsorption, is called:

Question 68 :
A solution of which substance can best be used as both titrant and its own indicator in an oxidation-reduction titration?

Question 69 :
Indigestion is painful so to relieve indigestion, we take anantacidsuch as milk of magnesia , which<br>contains :

Question 70 :
A red litmus paper when dipped in an aqueous solution of potassium acetate turned blue. Arrange the following steps in proper sequence to explain the above observation.<br>(a) Identification of spectator ions.<br>(b) Identification of free ions which caused the colour change of the litmus paper.<br>(c) Identification of positive and negative radicals.<br>(d) Writing the net reaction taking place<br>(e) Writing ionic equation for the reaction of positive and negative radicals with water.<br><br>

Question 71 :
The indicator used in the titration of iodine against sodium thiosulphate is

Question 72 :
The different colours of litmus in acidic, neutral and basic solutions are respectively: