Question

Monosaccharides have the general formula________.

• A. C[H2O]x
• B. [CH2O]x
• C. C2[H2O]x
• D. None

Hint:

The empirical formula \([CH_2O]_x\) is highly useful for identifying classic monosaccharides. However, keep in mind that some modified monosaccharides, such as deoxy sugars (e.g., deoxyribose, \(C_5H_{10}O_4\)), deviate slightly from this perfect ratio.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Monosaccharides are the simplest carbohydrate units, often referred to as simple sugars, which cannot be broken down into smaller carbohydrates by hydrolysis.
They serve as the basic building blocks for disaccharides, oligosaccharides, and polysaccharides.

Step 2: Detailed Explation:
The historical term "carbohydrate" arose because these organic compounds were observed to contain carbon, hydrogen, and oxygen in a ratio resembling hydrates of carbon.
The structural composition of a simple monosaccharide typically follows the empirical formula where for every carbon atom, there are two hydrogen atoms and one oxygen atom.
This composition is mathematically expressed by the general formula:
\[ [CH_2O]_x \]
where \(x\) represents an integer that is typically 3 or greater (usually ranging from 3 to 7).
For example:
- Trioses (such as glyceraldehyde) have \(x = 3\), giving \(C_3H_6O_3\).
- Pentoses (such as ribose) have \(x = 5\), giving \(C_5H_{10}O_5\).
- Hexoses (such as glucose and fructose) have \(x = 6\), giving \(C_6H_{12}O_6\).
All these structural representations can be simplified to the basic unit \([CH_2O]_x\).

Step 3: Fil Answer:
The general empirical formula representing monosaccharides is \([CH_2O]_x\).
Hence, the correct option is (B).