An element 'X' forms an oxide `XO_(2)`, which is a very useful gas used in photosynthesis process. The element is

Options

A. sulphur
B. nitrogen
C. carbon
D. phosphorus.

Explanation

To solve the question, we need to identify the element 'X' that forms the oxide \( XO_2 \), which is used in the photosynthesis process. Let's break this down step by step.

### Step 1: Understanding the oxide \( XO_2 \)
The oxide \( XO_2 \) indicates that the element 'X' combines with two oxygen atoms. This suggests that 'X' is likely a non-metal, as many non-metals form oxides with oxygen.

### Step 2: Identifying the gas used in photosynthesis
In the process of photosynthesis, plants utilize carbon dioxide (\( CO_2 \)) and water (\( H_2O \)) to produce glucose (\( C_6H_{12}O_6 \)) and oxygen (\( O_2 \)). The equation for photosynthesis is:
\[ 6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2 \]

### Step 3: Relating \( XO_2 \) to carbon dioxide
From the photosynthesis equation, we see that carbon dioxide (\( CO_2 \)) is a key reactant. The formula \( CO_2 \) matches the form \( XO_2 \), where 'X' must be carbon (C).

### Step 4: Conclusion
Since we have established that the oxide \( XO_2 \) corresponds to carbon dioxide (\( CO_2 \)), we can conclude that the element 'X' is carbon.

### Final Answer
The element 'X' is Carbon.

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