Podcast
Questions and Answers
What is the chemical opposite of acids?
What is the chemical opposite of acids?
All alkali are bases.
All alkali are bases.
True
Which of the following is a common alkali?
Which of the following is a common alkali?
What is the chemical formula for sodium hydroxide?
What is the chemical formula for sodium hydroxide?
Signup and view all the answers
What is the common name for calcium hydroxide?
What is the common name for calcium hydroxide?
Signup and view all the answers
Aqueous ammonia is a colorless gas.
Aqueous ammonia is a colorless gas.
Signup and view all the answers
Which of the following is a characteristic of alkalis?
Which of the following is a characteristic of alkalis?
Signup and view all the answers
Dilute alkalis turn moist red litmus paper blue.
Dilute alkalis turn moist red litmus paper blue.
Signup and view all the answers
What is the chemical formula for hydroxide ions?
What is the chemical formula for hydroxide ions?
Signup and view all the answers
Dissociation is the process by which a compound separates into ions.
Dissociation is the process by which a compound separates into ions.
Signup and view all the answers
What are two ways that alkalis can react with acids?
What are two ways that alkalis can react with acids?
Signup and view all the answers
What is the general ionic equation for the neutralization reaction?
What is the general ionic equation for the neutralization reaction?
Signup and view all the answers
The reaction between an alkali and a non-metal oxide always produces water.
The reaction between an alkali and a non-metal oxide always produces water.
Signup and view all the answers
What is the chemical formula for carbon dioxide?
What is the chemical formula for carbon dioxide?
Signup and view all the answers
What is the name of the salt formed when sodium hydroxide reacts with sulphur dioxide?
What is the name of the salt formed when sodium hydroxide reacts with sulphur dioxide?
Signup and view all the answers
Study Notes
Bases
- Bases are the chemical opposite of acids.
- Water-soluble bases are called alkalis. (Not all bases are alkalis)
- Common alkalis include sodium hydroxide (NaOH), potassium hydroxide (KOH), and calcium hydroxide (Ca(OH)₂).
- Sodium hydroxide is a white solid.
- Potassium hydroxide is a white solid.
- Calcium hydroxide (as a pure solid) is a white solid; in an aqueous form is known as lime water.
- Aqueous ammonia is a colorless gas.
Characteristics of Alkalis
- Alkalis have a bitter taste.
- Alkalis feel slippery, reacting with grease to form soap.
- Alkalis are electrolytes, meaning they release ions when dissolved in water.
- Dilute alkalis turn moist red litmus paper blue.
Role of Water in Bases
- When bases dissolve in water, they ionize, producing hydroxide ions (OH⁻).
- This ionization is what gives bases their alkaline properties.
Reaction of Bases (Neutralization)
- A base reacts with an acid to form a salt and water.
- This is known as neutralization.
Reaction of Bases with Non-metal Oxides
- Bases react with non-metal oxides like carbon dioxide (CO₂) and sulfur dioxide (SO₂), producing metal carbonates (or sulfites) and water.
- For example, calcium hydroxide (Ca(OH)₂) reacts with carbon dioxide (CO₂) to form calcium carbonate (CaCO₃) and water (H₂O).
Testing for Ammonium Ions
- To test if a salt contains ammonium ions (NH₄⁺), heat the salt with a base
- A pungent smell of ammonia gas (NH₃) indicates the presence of ammonium ions.
- The ammonia gas will turn moist red litmus paper blue.
Reaction of Alkalis with Salts
- Alkalis react with certain salts to form metal hydroxides and a new salt.
- This reaction can sometimes produce a precipitate.
- As an example, sodium hydroxide reacts with copper(II) chloride to form copper(II) hydroxide and sodium chloride.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on the properties and reactions of bases and alkalis. Explore concepts such as neutralization reactions, characteristics of alkalis, and their role in chemical reactions. Ideal for students studying chemistry.
