Q41 of 48 Page 15

What are strong and weak acids? In the following list of acids, separate strong acids from weak acids.

Hydrochloride acid, citric acid, acetic acid, nitric acid, formic acid, sulphuric acid.

Strong acids Acids that dissociates into hydrogen ions completely in an aqueous solution are strong acids. These hydrogen ions attach themselves to the water molecules producing a high concentration of H3O+ ions. Acids such as HCl, H2SO4 HNO3 are strong acids.


Weak acids Acids that do not dissociate completely into hydrogen ions in an aqueous solution are weak acids. Acids such as acetic acid and carbonic acid are weak acids.




















Strong acids



Weak acids



Hydrochloric acid



Citric acid



Nitric acid



Acetic acid



Sulphuric acid



Formic acid



More from this chapter

All 48 →
39

In one of the industrial process for manufacture of sodium hydroxide, a gas X is formed as by-product. The gas X reacts with lime water to give a compound Y which is used as a bleaching agent in chemical industry. Identify X and Y giving the chemical equation of the reaction involved.

 40

Fill in the missing data in the given table.























































Name of the salt



Formula



Salt obtained from



Base



Acid



(i)



Ammonium chloride



NH4Cl



NH4OH



-



(ii)



Copper sulphate



-



-



H2SO4



(iii)



Sodium chloride



NaCl



NaOH



-



(iv)



Magnesium nitrate



Mg(NO3)2



-



HNO3



(v)



Potassium sulphate



K2SO4



-



-



(vi)



Calcuim nitrate



Ca(NO3)2



Ca(OH)2



-



 42

When zinc metal is treated with a dilute solution of a strong acid, a gas is evolved, which is utilised in the hydrogenation of oil. Name the gas evolved. Write the chemical equation of the reaction involved and also write a test to detect the gas formed.

 43

In the following schematic diagram for the preparation of hydrogen gas as shown in the figure, what would happen if the following changes are made?



(a) In place of zinc granules, same amount of zinc dust is taken in the test tube.


(b) Instead of dilute sulphuric acid, dilute hydrochloric acid is taken.


(c) In place of zinc, copper turnings are taken.


(d) Sodium hydroxide is taken in place of dilute sulphuric acid and the tube is heated.