How is the concentration of hydroxide ions (OH–) affected when excess base is dissolved in a solution of sodium hydroxide?

>

>

Chapter 2 NCERT Class 10 Science SOLUTIONS

6. How is the concentration of hydroxide ions (OH–) affected when excess base is dissolved in a solution of sodium hydroxide?

Question:

How is the concentration of hydroxide ions (OH^–) affected when excess base is dissolved in a solution of sodium hydroxide?

Answer:

The concentration of hydroxide ions (OH^–) increases.

More NCERT Questions

Download Free PDF

(All Q's of this Chapter solved)

question pointer

Give two important uses of washing soda and baking soda.

question pointer

What is a neutralization reaction? Give two examples.

question pointer

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

question pointer

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?

question pointer

Fresh milk has a pH of 6. How do you think the pH will change as it turns into curd? Explain your answer.

question pointer

Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH3COOH) is added to test tube B. Amount and concentration taken for both the acids are same. In which test tube will the fizzing occur more vigorously and why?

question pointer

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.

question pointer

Why do acids not show acidic behaviour in the absence of water?

question pointer

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

question pointer

Compounds such as alcohols and glucose also contain hydrogen but are not categorized as acids. Describe an Activity to prove it.

question pointer

Write word equations and then balanced equations for the reaction taking place when :(a) dilute sulphuric acid reacts with zinc granules.(b) dilute hydrochloric acid reacts with magnesium ribbon.(c) dilute sulphuric acid reacts with aluminium powder.(d) dilute hydrochloric acid reacts with iron filings.

question pointer

Which one of the following types of medicines is used for treating indigestion? (a)Antibiotic (b) Analgesic (c) Antacid (d) Antiseptic

question pointer

10 mL of a solution of NaOH is found to be completely neutralised by 8 mL of a given solution of HCl. If we take 20 mL of the same solution of NaOH, the amount HCl solution (the same solution as before) required to neutralise it will be :

question pointer

A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains :

question pointer

A solution turns red litmus blue, its pH is likely to be : (a) 1 (b) 4 (c) 5 (d) 10

question pointer

Write an equation to show the reaction between Plaster of Paris and water.

question pointer

What will happen if a solution of sodium hydrogen carbonate is heated? Give the equation of the reaction involved.

question pointer

Name the sodium compound which is used for softening hard water.

question pointer

What is the common name of the compound CaOCl2?

question pointer

Under what soil condition do you think a farmer would treat the soil of his fields with quick lime (calcium oxide) or slaked lime (calcium hydroxide) or chalk (calcium carbonate)?

question pointer

Do basic solutions also have H+ (aq) ions? If yes, then why are these basic?

question pointer

What effect does the concentration of H+ (aq) ions have on the nature of the solution?

question pointer

You have two solutions, A and B. The pH of solution A is 6 and pH of solution B is 8. Which solution has more hydrogen ion concentration? Which of this is acidic and which one is basic?

question pointer

You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?

question pointer

How is the concentration of hydronium ions (H3O+) affected when a solution of an acid is diluted?

question pointer

While diluting an acid, why is it recommended that the acid should be added to water and not water to the acid?

question pointer

Why does dry HCl gas not change the colour of the dry litmus paper?

question pointer

Why does an aqueous solution of an acid conduct electricity?

question pointer

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

© 2026, Agrawal Group of Publications All rights reserved.