Molecular formula of pentahydroxy acid obtained when glucose is oxidised with `Br_(2)` water is

Options

A. `C_(6)H_(12)O_(7)`
B. `C_(6)H_(12)O_(8)`
C. `C_(6)H_(12)O_(6)`
D. `C_(6)H_(10)O_(6)`

Answer

To determine the molecular formula of the pentahydroxy acid obtained when glucose is oxidized with bromine water, we can follow these steps:

### Step 1: Identify the starting compound
The starting compound is glucose, which has the molecular formula \( C_6H_{12}O_6 \).

### Step 2: Understand the oxidation process
When glucose is oxidized with bromine water (\( Br_2 \) in water), it undergoes a reaction that converts it into gluconic acid. This process involves the oxidation of the aldehyde group in glucose to a carboxylic acid group.

### Step 3: Determine the structure of gluconic acid
Gluconic acid is a hexose sugar acid that retains five hydroxyl groups (–OH) and has one carboxylic acid group (–COOH). The structure of gluconic acid can be represented as follows:
- It has one carboxylic acid group and five hydroxyl groups.

### Step 4: Write the molecular formula for gluconic acid
The molecular formula for gluconic acid can be derived as follows:
- From glucose, we have 6 carbon atoms (C).
- The number of hydrogen atoms is 12, but one hydrogen is replaced by the carboxylic acid group, resulting in \( H_{12} - 1 = H_{11} \).
- The number of oxygen atoms increases from 6 in glucose to 7 in gluconic acid due to the addition of the carboxylic acid group.

Thus, the molecular formula for gluconic acid is:
\[ C_6H_{12}O_7 \]

### Step 5: Conclusion
The molecular formula of the pentahydroxy acid obtained when glucose is oxidized with bromine water is \( C_6H_{12}O_7 \).

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