Podcast
Questions and Answers
What is the pH value that indicates a neutral solution?
What is the pH value that indicates a neutral solution?
Which of the following describes a soluble base?
Which of the following describes a soluble base?
What is the chemical reaction between an acid and a base called?
What is the chemical reaction between an acid and a base called?
Which substance is commonly used to neutralise acidic soil?
Which substance is commonly used to neutralise acidic soil?
Signup and view all the answers
What color does red litmus paper turn when placed in an alkaline solution?
What color does red litmus paper turn when placed in an alkaline solution?
Signup and view all the answers
What is a defining property of acids?
What is a defining property of acids?
Signup and view all the answers
What is one way to control risks when handling corrosive solutions?
What is one way to control risks when handling corrosive solutions?
Signup and view all the answers
How does litmus paper indicate whether a solution is acidic or alkaline?
How does litmus paper indicate whether a solution is acidic or alkaline?
Signup and view all the answers
What characteristic do all alkalis share?
What characteristic do all alkalis share?
Signup and view all the answers
Which of the following acids is found in lemons?
Which of the following acids is found in lemons?
Signup and view all the answers
What is the general pH range of acids?
What is the general pH range of acids?
Signup and view all the answers
Which of the following substances is an example of an alkali?
Which of the following substances is an example of an alkali?
Signup and view all the answers
What can be inferred about bases in relation to alkalis?
What can be inferred about bases in relation to alkalis?
Signup and view all the answers
Study Notes
Acids and Alkalis
- Acids: Substances containing hydrogen, often liquids, that react with other substances to form salts. Some can burn or dissolve materials. Acids have a pH lower than 7 and taste sour. Examples include hydrochloric acid (in stomach), ethanoic acid (in vinegar), and citric acid (in lemons). Lab acids are corrosive.
- Alkalis: The chemical opposite of acids. They feel soapy and are bases. Examples include soap solutions and toothpaste. Lab alkalis are corrosive. Not all bases are alkalis.
- Corrosive: Substances that can burn or damage skin and eyes. Acids and alkalis can be corrosive.
- Concentrated: A high amount of solute (acid or alkali) dissolved in a solvent (usually water).
- Dilute: A low amount of solute dissolved in a solvent.
- Hazard Symbols: Warnings on chemicals indicating potential harm (e.g., corrosive, irritant).
Indicators and pH Scale
- Indicators: Substances that change color depending on whether a solution is acidic or alkaline. Red cabbage juice is a natural indicator.
- Litmus: A solution of dyes from lichens. Litmus paper (red and blue) responds to acids and alkalis (e.g., red litmus turns blue in alkalis, blue litmus remains blue in acids).
- Universal Indicator: A mixture of dyes that changes color to show the acidity or alkalinity of a solution.
- pH Scale: A scale measuring acidity or alkalinity. Pure water (neutral) is pH 7. Lower numbers indicate acidity, higher numbers indicate alkalinity.
Neutralization
- Neutralization: The chemical reaction between an acid and an alkali.
- Base: A substance that neutralizes an acid. Some bases dissolve in water (these are called alkalis).
- pH 7: Neutral pH.
- Uses of Neutralization: Dock leaves, quicklime/calcium oxide for soil, calcium hydroxide for factory waste, relief creams (for stings, acid/alkali treatment) and antacids for indigestion.
Making Salts
- Salt: A substance formed when an acid reacts with a metal or a metal-containing compound.
- Example: Copper sulfate crystals can be formed through such a reaction.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on acids, alkalis, and their properties. This quiz covers definitions, examples, and the pH scale, providing insight into chemical reactions and safety. Perfect for students looking to reinforce their understanding of basic chemistry concepts.
