Which of the following statements is true?

Question

Prepp Team · Accepted Answer

Understanding the Properties of Acids and Bases

Acids and bases are common chemical substances found around us. They have distinct physical and chemical properties that help us identify them. This question asks us to identify a true statement among the given options regarding the properties of acids and bases, particularly focusing on their taste and how they interact with indicators like litmus paper.

Analyzing Each Statement on Acid and Base Properties

Let's examine each statement carefully to determine its accuracy based on the known properties of acids and bases.

Statement 1: Bases are bitter in taste.
This statement describes the typical taste of bases. Many common bases, like soap or baking soda solutions, are known to have a bitter taste.
Statement 2: Acids change the colour of red litmus to blue.
Litmus paper is a common indicator used to distinguish between acids and bases. Acids are known to change the color of blue litmus paper to red, not red litmus to blue. Bases are the substances that change red litmus to blue.
Statement 3: Acids are salty in taste.
Acids are typically known for their sour taste, not salty. For example, citrus fruits contain citric acid and taste sour.
Statement 4: Bases change the colour of the blue litmus to red.
As mentioned earlier, bases change the color of red litmus paper to blue. Acids change blue litmus paper to red. This statement is the opposite of what bases do to blue litmus.

Identifying the Correct Statement About Bases and Acids

Based on the analysis, let's revisit the properties:

Acids are typically sour in taste.
Bases are typically bitter in taste.
Acids turn blue litmus red.
Bases turn red litmus blue.

Comparing these facts with the given statements:

Statement 1 says Bases are bitter in taste. This aligns with the known property of bases.
Statement 2 says Acids change red litmus to blue. This is incorrect; acids turn blue litmus red.
Statement 3 says Acids are salty in taste. This is incorrect; acids are sour.
Statement 4 says Bases change blue litmus to red. This is incorrect; bases turn red litmus blue.

Therefore, the only true statement among the options provided is that bases are bitter in taste.

Summary of Acid and Base Properties

Here's a quick summary of the general properties discussed:

Property	Acids	Bases
Taste	Sour	Bitter
Litmus Test (Blue Litmus)	Turns Red	No Change
Litmus Test (Red Litmus)	No Change	Turns Blue

Revision Table: Key Differences Between Acids and Bases

Understanding the fundamental differences between acids and bases is crucial for chemistry. Here is a table summarizing some key characteristics:

Characteristic	Acid	Base
Taste	Sour	Bitter
Touch	Burn skin (Strong acids)	Soapy/Slippery (Strong bases)
Effect on Blue Litmus	Turns Red	No Effect
Effect on Red Litmus	No Effect	Turns Blue
pH Level	Below 7	Above 7
Reaction with Metals	Often produces hydrogen gas	Some react, some don't
Neutralization	Reacts with bases to form salt and water	Reacts with acids to form salt and water

Additional Information on Acids, Bases, and Indicators

It is important to note that tasting acids or bases, especially concentrated ones, is extremely dangerous and should never be attempted. Taste is a property used for very dilute or naturally occurring substances like food items.

Chemical indicators like litmus paper are safe ways to test whether a substance is acidic or basic. Litmus is a natural dye extracted from lichens. There are other indicators too, like phenolphthalein and methyl orange, which change color at different pH ranges.

The strength of an acid or base is measured using the pH scale, which ranges from 0 to 14. A pH below 7 indicates an acid, a pH above 7 indicates a base, and a pH of 7 indicates a neutral substance (like pure water).