Q1. You are given three test tubes A, B and C containing different colourless solution A is filled with Sulphuric acid solution, B is filled with magnesium hydroxide solution and C is filled with mixture of equal concentration of both the solutions as filled in A and B. Few drops of phenolphthalein is added in each of the test tubes. Identify the changes observed.
(a) A and B remain colourless, C becomes pink
(b) A and C remain colourless, B becomes pink
(c) B and C remain colourless, A becomes pink
(d) A remains colourless, B and C becomes pink
Q2. Which of the following living beings is not a source of in that differentiate between acids and bases by changing colour ?
(a) Turmeric .
(b) China rose
(c) Lichens
(d) Lotus
Q3. Which of the following synthetic indicators turns red in a basic medium and turn yellow in an acidic medium?
(a) Phenolphthalein
(b) Methyl orange
(c) Phenol red
(d) Methyl red
Q4. During an experiment phenolphthalein is added to an acid solution. After that a basic solution is added dropwise until the complete neutralisation of acid occurs. If one more drop of the basic solution added, then the colour of the acid containing solution would turn to
(a) colourless
(b) yellow
(c) red .
(d) pink
Q5. Which of the following indicators cannot differentiate between a neutral solution and an acidic solution?
(a) Phenolphthalein
(b) Litmus
(c) Methyl orange
(d) Methyl red
Q6. In the following tables identify colours that can suitably replace the alphabets p, q and r mark your response using the codes that follow:
|
Indicator
|
Colour
|
|
|
|
Acidic Medium
|
Basic medium
|
|
I. Turmeric
|
Yellow
|
P
|
|
II. China rose
|
Q
|
Green
|
|
III. Methyl orange
|
Red
|
R
|
Codes
P Q R
(a) Red Yellow Yellow
(b) Red Pink Yellow
(c) Pink Blue Red
(d) Orange Colourless Red
Q7. Which of the following acts as a natural indicator for pollution in water?
(a) Lichens
(b) Algae
(c) China rose plant
(d) Fungi
Q8. In the alternatives that follow a cure has been suggested against each of the given daily life problem. Identify the alternative with in appropriate suggestion.
(a) Influenza – milk of magnesia
(b) Ant’s sting – vinegar
(c) Acidic soil – HCl
(d) None of these
Q9. If a strong base reacts with equally strong acid, then what would be the nature of the resulting solution?
(a) Slightly acidic
(b) Slightly basic
(c) Neutral
(d) Cannot be predicted
Q10. Which of the following salts is formed when by the neutralisation of a strong acid by a weak base?
(a) Sodium chloride
(b) Ammonium chloride
(c) Sodium phosphate
(d) Ammonium phosphate
Solutions:
S1. Ans.(b)
S2. Ans.(d)
S3. Ans.(c)
S4. Ans.(d)
S5. Ans.(a)
S6. Ans.(b)
S7. Ans.(a)
S8. Ans.(b)
S9. Ans.(c)
S10. Ans.(b)
