Question:
Consider the following statements:
(a) Both acids and bases change colour of all indicators.
(b) If an indicator gives a colour change with an acid, it does not give a change with a base.
(c) If an indicator changes colour with a base, it does not change colour with an acid.
(d) Change of colour in an acid and a base depends on the type of the indicator.

Which of these statements are correct?
(i) All four (ii) a and d (iii) b and c (iv) only d

Answer:

(iv) only d

Change of the colour in an acid or the base depends on the type of the indicator. It is so because we know that a basic solution do not change the colour of the blue litmus paper whereas the acid does. The acidic solution do not change the colour of the red litmus paper whereas the basic solution does.

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