Acids, Bases and Salts — Class 10 Science PYQs

When $2\text{ mL}$ of sodium hydroxide solution is added to few pieces of granulated zinc in a test tube and then warmed, the reaction that occurs can be written in the form of a balanced chemical equation as :

Juice of tamarind turns blue litmus to red. It is because of the presence of an acid called :

Consider the following compounds :
${\text{FeSO}}_4$ ; ${\text{CuSO}}_4$ ; ${\text{CaSO}}_4$ ; ${\text{Na}}_2{\text{CO}}_3$

The compound having maximum number of water of crystallisation in its crystalline form in one molecule is :

Tooth decay begins at the pH of :

(i) The pH of a sample of tomato juice is $4.6$. How is this juice likely to be in taste ? Give reason to justify your answer.
(ii) How do we differentiate between a strong acid and a weak base in terms of ion-formation in aqueous solutions ?
(iii) The acid rain can make the survival of aquatic animals difficult. How ?

A compound which is prepared from gypsum has the property of hardening when water is mixed in right quantity with it :
(i) Write common name and the chemical name of this compound.
(ii) Give chemical equation for its preparation.
(iii) List its two uses.

Salts play a very important role in our daily life. Sodium chloride which is known as common salt is used almost in every kitchen. Baking soda is also a salt used in faster cooking as well as in baking industry. The family of salts is classified on the basis of cations and anions present in them.

(a) Identify the acid and base from which Sodium chloride is formed.
(b) Find the cation and the anion present in Calcium sulphate.
(c) "Sodium chloride and washing soda both belong to the same family of salts." Justify this statement.

OR

(c) Define the term pH scale. Name the salt obtained by the reaction of Potassium hydroxide and Sulphuric acid and give the pH value of its aqueous solution.

Salts play a very important role in our daily life. Sodium chloride which is known as common salt is used almost in every kitchen. Baking soda is also a salt used in faster cooking as well as in baking industry. The family of salts is classified on the basis of cations and anions present in them.

(a) Identify the acid and base from which Sodium chloride is formed.
(b) Find the cation and the anion present in Calcium sulphate.
(c) “Sodium chloride and washing soda both belong to the same family of salts.” Justify this statement.

OR

(c) Define the term pH scale. Name the salt obtained by the reaction of Potassium hydroxide and Sulphuric acid and give the pH value of its aqueous solution.