Question

indicators.
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(c) Acids produce.
ions on dissolving in water.
(d) Those substances whose smell (or odour) changes in acidic or basic solutions are called
(e) Onion and vanilla extract are.
indicators.
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Short Answer Type Questions
16. (a) What is an indicator ? Name three common indicators.
(b) Name the acid-base indicator extracted from lichen.
(c) What colour does the turmeric paper turn when put in an alkaline solution ?
17. What is an olfactory indicator ? Name two olfactory indicators. What is the effect of adding sodium hydroxide
solution to these olfactory indicators ?
18. (@) What happens when an acid reacts with a metal ? Give chemical equation of the reaction involved.
(b) Which gas is usually liberated when an acid reacts with a metal ? How will you test for the presence of
this gas?
19. While diluting an acid, why is it recommended that the acid should be added to water and not water to the
acid ?
20. What happens when an acid reacts with a metal hydrogencarbonate ? Write equation of the reaction which
takes place.
21. (a) What happens when dilute hydrochloric acid is added to sodium carbonate ? Write a balanced chemic
equation of the reaction involved.
(b) Which gas is liberated when dilute hydrochloric acid reacts with sodium carbonate ? How will you t
for the presence of this gas?
22. What happens when an acid reacts with a base ? Explain by taking the example of hydrochloric acid a
sodium hydroxide. Give equation of the chemical reaction which takes place. What is the special nam
such a reaction ?
23. What happens when an acid reacts with a metal oxide ? Explain with the help of an example. Wr
balanced equation for the reaction involved.
24. (a) What are organic acids and mineral acids ?
(b) Give two examples each of organic acids and mineral acids.
(C) State some of the uses of mineral acids in industry.
25. What is meant by strong acids and weak acids ? Classify the following into strong acids and weak a
HCI, CH,COOH, H SO, HNO H.CO, H,SO
26. Why do HCI, H SO, HINO, etc., show acidic character in aqueous solutions while solutions of com-
like C,H120. (glucose) and C,H,OH (alcohol) do not show acidic character ?
27. What is a neutralisation reaction ? Explain with an example. Give the chemical equation of the​

Answer 1

Answer:

(a) Acids have a sour taste and they turn blue litmus to red.

(b) Substances do not show their acidic properties without water .

(c) Acid produces hydrogen ions on dissolving in water.

(d) Those substances whose smell (or odour) changes in acidic or basic solutions are called olfactory.

(e) Onion and vanilla extract are olfactory.