Class 10 Science - Chapter Acids, Bases and Salts NCERT Solutions | What is a neutralisation reaction? Give

Why does distilled water not conduct electricity, whereas rain water does?

Plaster of Paris should be stored in a moisture-proof container. Explain why?

A solution turns red litmus blue, its pH is likely to be

  (a) 1          (b) 4          (c) 5          (d) 10

Give two important uses of washing soda and baking soda.

Why do HCl, HNO₃, etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?

Why should curd and sour substances not be kept in brass and copper vessels?

Which gas is usually liberated when an acid reacts with a metal? Illustrate with an example. How will you test for the presence of this gas?

Five solutions A,B,C,D and E when tested with universal indicator showed pH as 4,1,11,7 and 9, respectively. Which solution is

(a) neutral?
(b) strongly alkaline?
(c) strongly acidic?
(d) weakly acidic?
(e) weakly alkaline?

Arrange the pH in increasing order of hydrogen-ion concentration.

Name the substance which on treatment with chlorine yields bleaching powder.

A milkman adds a very small amount of baking soda to fresh milk.

   (a) Why does he shift the pH of the fresh milk from 6 to slightly alkaline?
   (b) Why does this milk take a long time to set as curd?

Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.

What is a good source of energy?

Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?

What are trophic levels? Give an example of a food chain and state the different trophic levels in it.

What changes can you make in your habits to become more environment-friendly?

What is the difference between a reflex action and walking?

What is the importance of DNA copying in reproduction?

If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

Why should a magnesium ribbon be cleared before burning in air?

Define the principal focus of a concave mirror.

Why are human beings who look so different from each other in terms of size, colour and looks said to belong to the same species?

What are the differences between the transport of materials in xylem and phloem?

Why do ionic compounds have high melting points?

You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.

How does chemical coordination take place in animals?

What is a balanced chemical equation? Why should chemical equations be balanced?

If all the waste we generate is biodegradable, will this have no impact on the environment?

How many structural isomers can you draw for pentane?

Most of the sources of energy we use represent stored solar energy. Which of the following is not ultimately derived from the Sun’s energy?

      (a) geothermal energy            (b) wind energy
      (c) nuclear energy                  (d) bio-mass.

Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents such as ethanol also?