Podcast
Questions and Answers
Substances that taste sour contain ______.
Substances that taste sour contain ______.
acids
The chemical nature of substances that contain acids is ______.
The chemical nature of substances that contain acids is ______.
acidic
Substances that are bitter in taste and feel soapy are known as ______.
Substances that are bitter in taste and feel soapy are known as ______.
bases
The nature of substances that are bitter and soapy is described as ______.
The nature of substances that are bitter and soapy is described as ______.
[Blank] are used to test whether a substance is acidic or basic.
[Blank] are used to test whether a substance is acidic or basic.
Indicators show a change in ______ when added to acidic or basic solutions.
Indicators show a change in ______ when added to acidic or basic solutions.
[Blank], litmus, and China rose petals are examples of naturally occurring indicators.
[Blank], litmus, and China rose petals are examples of naturally occurring indicators.
[Blank] is a commonly used natural indicator extracted from lichens.
[Blank] is a commonly used natural indicator extracted from lichens.
Litmus turns ______ in an acidic solution and blue in a basic solution.
Litmus turns ______ in an acidic solution and blue in a basic solution.
Solutions that do not change the color of either red or blue litmus are known as ______ solutions.
Solutions that do not change the color of either red or blue litmus are known as ______ solutions.
Neutral solutions are neither ______ nor basic.
Neutral solutions are neither ______ nor basic.
China rose indicator turns acidic solutions to dark ______ and basic solutions to green.
China rose indicator turns acidic solutions to dark ______ and basic solutions to green.
Acid rain contains excess acids and is formed when pollutants like sulphur dioxide and nitrogen dioxide dissolve in ______.
Acid rain contains excess acids and is formed when pollutants like sulphur dioxide and nitrogen dioxide dissolve in ______.
Acids and bases are ______ in nature and should be handled with care.
Acids and bases are ______ in nature and should be handled with care.
When an acid and a base are mixed, they neutralize each other; this process is called ______.
When an acid and a base are mixed, they neutralize each other; this process is called ______.
In a neutralisation reaction, ______ is always produced or evolved.
In a neutralisation reaction, ______ is always produced or evolved.
In neutralisation, a new substance called ______ is formed, which can be acidic, basic, or neutral.
In neutralisation, a new substance called ______ is formed, which can be acidic, basic, or neutral.
The reaction between an acid and a base is known as neutralisation, producing salt and ______.
The reaction between an acid and a base is known as neutralisation, producing salt and ______.
Our stomach contains hydrochloric acid to help digest food, but too much acid can cause ______.
Our stomach contains hydrochloric acid to help digest food, but too much acid can cause ______.
Antacids, like milk of magnesia, contain ______ hydroxide to neutralise the effect of excessive acid in the stomach.
Antacids, like milk of magnesia, contain ______ hydroxide to neutralise the effect of excessive acid in the stomach.
When an ant bites, it injects ______ acid into the skin.
When an ant bites, it injects ______ acid into the skin.
Excessive use of chemical fertilisers can make the soil ______.
Excessive use of chemical fertilisers can make the soil ______.
Acidic soil is treated with bases like quick lime (calcium ______) or slaked lime (calcium hydroxide).
Acidic soil is treated with bases like quick lime (calcium ______) or slaked lime (calcium hydroxide).
If the soil is basic, ______ matter is added to neutralise the soil.
If the soil is basic, ______ matter is added to neutralise the soil.
Factory wastes containing acids are neutralised by adding ______ substances before disposal.
Factory wastes containing acids are neutralised by adding ______ substances before disposal.
______, lemon juice, and orange juice taste sour because they contain acids.
______, lemon juice, and orange juice taste sour because they contain acids.
The word acid comes from the Latin word ______, which means sour.
The word acid comes from the Latin word ______, which means sour.
Litmus is available as ______ and blue.
Litmus is available as ______ and blue.
The effect of the formic acid from an ant bite can be neutralised by rubbing moist baking soda or ______ solution.
The effect of the formic acid from an ant bite can be neutralised by rubbing moist baking soda or ______ solution.
Factory wastes are neutralised by adding ______ substances.
Factory wastes are neutralised by adding ______ substances.
The rain becomes _______ because carbon dioxide, sulphur dioxide and nitrogen dioxide dissolve in rain drops.
The rain becomes _______ because carbon dioxide, sulphur dioxide and nitrogen dioxide dissolve in rain drops.
_______ rains is the name indicates the rain containing excess of acids.
_______ rains is the name indicates the rain containing excess of acids.
Excessive use of _______ makes the soil acidic.
Excessive use of _______ makes the soil acidic.
The effect of the acid can be neutralised by rubbing moist _______
The effect of the acid can be neutralised by rubbing moist _______
A _______ is found in many household products, such as window cleaners.
A _______ is found in many household products, such as window cleaners.
Commonly _______ is extracted from lichens
Commonly _______ is extracted from lichens
_______ is a substance which shows different colours in acidic and basic.
_______ is a substance which shows different colours in acidic and basic.
_______ is natural indicator extract from the lichens.
_______ is natural indicator extract from the lichens.
_______ is another natural indicator.
_______ is another natural indicator.
Flashcards
What are acids?
What are acids?
Substances whose solutions taste sour are acids. Their chemical nature is acidic.
What are Bases?
What are Bases?
Substances that are bitter and feel soapy to touch are bases. Their nature is called basic.
What are indicators?
What are indicators?
Special substances used to test if a substance is acidic or basic.
What is litmus?
What is litmus?
Signup and view all the flashcards
What are neutral solutions?
What are neutral solutions?
Signup and view all the flashcards
What is Neutralization?
What is Neutralization?
Signup and view all the flashcards
What is Acid Rain?
What is Acid Rain?
Signup and view all the flashcards
What is Indigestion?
What is Indigestion?
Signup and view all the flashcards
What are Antacids?
What are Antacids?
Signup and view all the flashcards
What can acid rain cause?
What can acid rain cause?
Signup and view all the flashcards
Study Notes
- Many substances used daily have different tastes, like sour, bitter, sweet, and salty
Acids and Bases
- Sour-tasting substances like curd, lemon juice, orange juice, and vinegar contain acids
- The chemical nature of these substances is acidic
- The word "acid" comes from the Latin word "acere," which means sour
- Acids in these substances are natural acids
- Baking soda does not taste sour, indicating it does not contain acids and has a bitter taste
- Substances with a bitter taste that feel soapy are known as bases, and their nature is basic
- Indicators test whether a substance is acidic or basic
- Indicators change color when added to acidic or basic solutions
- Turmeric, litmus, and China rose petals (Gudhal) are naturally occurring indicators
Natural Indicators
-
Litmus, a natural dye, is a commonly used natural indicator extracted from lichens
-
Litmus has a mauve (purple) color in distilled water
-
Litmus turns red when added to an acidic solution
-
Litmus turns blue when added to a basic solution
-
Litmus is available as a solution or as strips of paper called litmus paper
-
Litmus paper is generally found as red and blue strips
-
Acetic acid is found in vinegar
-
Formic acid is found in ant stings
-
Citric acid is found in citrus fruits like oranges and lemons
-
Lactic acid is found in curd
-
Oxalic acid is found in spinach
-
Ascorbic acid (Vitamin C) is found in Amla and citrus fruits
-
Tartaric acid is found in tamarind, grapes, and unripe mangoes
-
All the above acids occur naturally
-
Calcium hydroxide is found in lime water
-
Ammonium hydroxide is found in window cleaner
-
Sodium hydroxide and Potassium hydroxide and found in soap
-
Magnesium hydroxide is found in Milk of magnesia
Activity: Testing with Litmus Paper
- Mix a substance with water
- Put a drop of the solution on red litmus paper
- Observe any color change
- Repeat the process with blue litmus paper
- Solutions that do not change the color of either red or blue litmus paper are neutral solutions
- Neutral solutions are neither acidic nor basic
Turmeric as an Indicator
- Turmeric powder can be made into a paste with water
- Turmeric paste can be deposited on blotting paper or filter paper and dried to create turmeric paper
- Applying a drop of soap solution on turmeric paper will cause it to change color
- Lime water created by adding lime (chuna) to water, stirring, and pouring from the top
China Rose as an Indicator
- Collect China rose (Gudhal) petals and place them in a beaker with warm water
- The colored water can be used as an indicator
- Acidic solutions turn dark pink (magenta)
- Basic solutions turn green
Acid Rain
- Acid rain contains excess acids
- Carbon dioxide, sulfur dioxide, and nitrogen dioxide (released as pollutants) dissolve in raindrops and cause rain to be acidic
- They form carbonic acid, sulfuric acid, and nitric acid
- Acid rain can damage buildings, historical monuments, plants, and animals
Neutralization
- Acids turn blue litmus red, and bases turn red litmus blue
- Mixing an acidic solution with a basic solution neutralizes the effects of each other
- Mixing an acid and a base in suitable amounts destroys their acidic and basic natures, resulting in a neutral solution
- Neutralization reactions produce heat
- A new substance called salt is formed
- Salts can be acidic, basic, or neutral
- Neutralization: The reaction between an acid and a base, producing salt and water with the evolution of heat
- Example: Hydrochloric acid (HCl) + Sodium hydroxide (NaOH) → Sodium chloride (NaCl) + Water (H₂O)
Neutralization in Everyday Life
- Indigestion: Hydrochloric acid in the stomach aids digestion, but too much causes indigestion
- Antacids, like milk of magnesia (magnesium hydroxide), neutralize the excessive acid
- Ant bites: Inject acidic liquid (formic acid) into the skin
- Rubbing moist baking soda (sodium hydrogencarbonate) or calamine solution (zinc carbonate) neutralizes it
- Soil treatment: Excessive use of chemical fertilizers makes the soil acidic
- Plants do not grow well in overly acidic or basic soil which is why the treatment of soil is important
- Acidic soil gets treated with bases like quick lime (calcium oxide) or slaked lime (calcium hydroxide)
- Basic soil gets treated with organic matter (compost), which releases acids to neutralize the soil's basic nature
- Factory wastes: Contain acids that must be neutralized with basic substances before flowing into water bodies to prevent harm to aquatic life
Keywords
- Acid: A substance with a sour taste
- Acidic: Having the properties of an acid
- Base: A substance with a bitter taste and soapy feel
- Basic: Having the properties of a base
- Indicator: A substance that shows different colors in acidic, basic, and neutral solutions
- Neutral: Neither acidic nor basic
- Neutralization: The reaction between an acid and a base
- Salt: A substance formed in a neutralization reaction
Key Points
- Acids taste sour, and bases taste bitter and feel soapy
- Acids turn blue litmus red, and bases turn red litmus blue
- Neutral substances are neither acidic nor basic
- Indicators show different colors in acidic, basic, and neutral solutions
- Acids and bases neutralize each other to form a salt, which can be acidic, basic, or neutral
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Explore acids, bases, and indicators. Acids taste sour and are found in substances like lemon juice. Bases taste bitter & feel soapy. Indicators like litmus and turmeric help identify acids and bases by changing color.
