
The acidity of calcium hydroxide is _______.
(A) 2
(B) 1
(C) 3
(D) 4
Answer
151.2k+ views
Hint: On determining pH of a solution, we can find out whether the substance is acidic or basic in nature. So, the number of ions are the factors responsible for calculating the acidity or basicity of any compound.
Complete step-by-step solution:
Calcium hydroxide is commonly known as slaked lime. It is an inorganic compound having formula and is colourless in its hexagonal crystalline form. There exists an ionic bond between the calcium and two hydroxide ions. Direct exposure to concentrated can affect lungs and might even lead to blindness.
It is chemically very reactive. When it is dissolved in water till a saturation point, it produces a solution called limewater (CaO), which acts as a moderate base. Limewater reacts with many acids and forms salts. The saturated solution of calcium hydroxide in water can also react with metal and dissolves them. For example, aluminium. It also reacts with carbon dioxide and forms calcium carbonate . This reaction is commonly known as carbonatation.
Calcium hydroxide releases hydroxide ions when dissolved in aqueous solutions. The liberation of ions due to electrocyclic dissociation confirms that it is a base. The number of ionizable hydroxide ions that are present in one molecule of base is termed as the acidity of bases. On that basis, they are classified into three different types: monoacidic, diacidic and triacidic.
Therefore, in case of calcium hydroxide, it has two hydroxide ions which dissociate when dissolved in an aqueous medium. This makes it acidic in nature and results in the acidity of the compound.
As there are 2 hydroxide ions present in the solution, the acidity of caustic soda is 2. It is a diacidic base.
Hence, the correct option is (A).
Note: As acidity of a base depends upon the number of free hydroxyl ions released in the solution, similarly we can find out the basicity of an acid which depends upon the number of free hydrogen ions released in the solution when dissolved in water. For example, the basicity of is 3.
Complete step-by-step solution:
Calcium hydroxide is commonly known as slaked lime. It is an inorganic compound having formula
It is chemically very reactive. When it is dissolved in water till a saturation point, it produces a solution called limewater (CaO), which acts as a moderate base. Limewater reacts with many acids and forms salts. The saturated solution of calcium hydroxide in water can also react with metal and dissolves them. For example, aluminium. It also reacts with carbon dioxide and forms calcium carbonate
Calcium hydroxide releases hydroxide ions when dissolved in aqueous solutions. The liberation of
Therefore, in case of calcium hydroxide, it has two hydroxide ions which dissociate when dissolved in an aqueous medium. This makes it acidic in nature and results in the acidity of the compound.
As there are 2 hydroxide ions present in the solution, the acidity of caustic soda is 2. It is a diacidic base.
Hence, the correct option is (A).
Note: As acidity of a base depends upon the number of free hydroxyl ions released in the solution, similarly we can find out the basicity of an acid which depends upon the number of free hydrogen ions released in the solution when dissolved in water. For example, the basicity of
Latest Vedantu courses for you
Grade 8 | CBSE | SCHOOL | English
Vedantu 8 CBSE Pro Course - (2025-26)
School Full course for CBSE students
₹45,300 per year
EMI starts from ₹3,775 per month
Recently Updated Pages
Types of Solutions - Solution in Chemistry

Difference Between Crystalline and Amorphous Solid

JEE Main Participating Colleges 2024 - A Complete List of Top Colleges

JEE Main Maths Paper Pattern 2025 – Marking, Sections & Tips

Sign up for JEE Main 2025 Live Classes - Vedantu

JEE Main 2025 Helpline Numbers - Center Contact, Phone Number, Address

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

Degree of Dissociation and Its Formula With Solved Example for JEE

JEE Main 2025: Conversion of Galvanometer Into Ammeter And Voltmeter in Physics

Electrical Field of Charged Spherical Shell - JEE

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

JEE Advanced 2025: Dates, Registration, Syllabus, Eligibility Criteria and More

JEE Advanced Weightage 2025 Chapter-Wise for Physics, Maths and Chemistry

Thermodynamics Class 11 Notes: CBSE Chapter 5

NCERT Solutions for Class 11 Chemistry In Hindi Chapter 1 Some Basic Concepts of Chemistry

Learn About Angle Of Deviation In Prism: JEE Main Physics 2025
