Which general formula can be used to identify carbohydrates?

• A. \(C_nH_{2n-2}O_n\)
• B. \(C_nH_{2n}O_{2n}\)
• C. \(C_n(H_2O)_n\)
• D. \(C_nH_{2n+2}O_n\)

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the definition of carbohydrates. Carbohydrates are organic molecules composed of carbon (C), hydrogen (H), and oxygen (O) atoms, typically in a ratio that reflects the general formula (CH2O)n.
2. Step 2: Analyze the given formulas. Each formula represents a different arrangement of carbon, hydrogen, and oxygen atoms. Compare these formulas to the typical structure of carbohydrates.
3. Step 3: Recall that carbohydrates are often referred to as 'hydrates of carbon,' meaning their structure can be simplified to a repeating unit of (CH2O). This is why the correct general formula for carbohydrates is Cn(H2O)n.
4. Step 4: Evaluate the incorrect options. For example, \(C_nH_{2n-2}O_n\) and \(C_nH_{2n+2}O_n\) do not match the typical ratio of hydrogen to oxygen found in carbohydrates. Similarly, \(C_nH_{2n}O_{2n}\) suggests an excess of oxygen, which is not characteristic of carbohydrates.
5. Step 5: Conclude that the correct general formula for identifying carbohydrates is \(C_n(H_2O)_n\), as it accurately represents the molecular structure and ratio of elements in carbohydrates.