Exploring Substances: Acidic, ...
1/19
What are acids?
Acids are substances that release hydrogen ions (H⁺) in solution and have a pH less than 7.
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2/19
What are bases?
Bases are substances that release hydroxide ions (OH⁻) in solution and have a pH greater than 7.
3/19
What is a neutral substance?
A neutral substance has a pH of 7 and does not change litmus paper color.
4/19
What is the pH scale?
The pH scale ranges from 0 to 14, measuring the acidity or basicity of a substance.
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What is litmus paper used for?
Litmus paper is used to test whether a substance is acidic or basic; it turns red in acidic solutions and blue in basic ones.
6/19
Name common acids.
Common acids include hydrochloric acid (HCl), sulfuric acid (H₂SO₄), and acetic acid (found in vinegar).
7/19
Name common bases.
Common bases include sodium hydroxide (NaOH), potassium hydroxide (KOH), and calcium hydroxide (lime).
8/19
What is neutralization?
Neutralization is a chemical reaction between an acid and a base, producing salt and water.
9/19
Give an example of a neutralization reaction.
Hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH) to produce sodium chloride (table salt) and water.
10/19
What happens to blue litmus paper in acid?
Blue litmus paper turns red when exposed to an acidic solution.
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What happens to red litmus paper in a base?
Red litmus paper turns blue when exposed to a basic solution.
12/19
Name other indicators besides litmus.
Other indicators include phenolphthalein (turns pink in basic solutions) and universal indicator (shows a range of colors).
13/19
What can affect the pH of a solution?
Factors include the presence of acids or bases, dilution, and temperature.
14/19
Why is pH important in everyday life?
pH is important for processes like digestion, soil health, and the functioning of aquatic ecosystems.
15/19
What safety measures should you take when handling acids/bases?
Always wear gloves and goggles, work in a well-ventilated area, and read labels before use.
16/19
What is a common mistake regarding acids and bases?
A common mistake is assuming all bases are safe; some are very caustic and harmful.
17/19
How do acids and bases differ in taste?
Acids generally have a sour taste, while bases feel slippery and may taste bitter.
18/19
What happens when you mix acids and bases?
They can neutralize each other, often producing heat and forming water and salts.
19/19
Do all acids release H⁺ ions?
Yes, all acids in aqueous solutions release hydrogen ions H⁺, which defines their acidic nature.
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