Catalytic dehydrogenation of n-heptane in presence of `Cr_2O_3//Al_2O_3` at 750 K gives

Options

A. Iso-heptane
B. 1-heptane
C. Toluene
D. 2,3-dimethylpentene-1

Explanation

To solve the question regarding the catalytic dehydrogenation of n-heptane in the presence of Cr2O3/Al2O3 at 750 K, we can follow these steps:

### Step 1: Understand the Reaction
Catalytic dehydrogenation is a process where hydrogen is removed from a hydrocarbon in the presence of a catalyst. In this case, n-heptane (C7H16) will undergo dehydrogenation.

### Step 2: Write the Chemical Equation
The dehydrogenation of n-heptane can be represented by the following equation:
\[ \text{C}_7\text{H}_{16} \rightarrow \text{C}_7\text{H}_{14} + \text{H}_2 \]
Here, n-heptane (C7H16) is converted to heptene (C7H14) and hydrogen gas (H2).

### Step 3: Identify the Product
Since n-heptane is a straight-chain alkane, the product of its dehydrogenation will be an alkene. The most common product formed from the dehydrogenation of n-heptane is 1-heptene or 2-heptene, depending on the reaction conditions and the catalyst used.

### Step 4: Conclusion
Thus, the catalytic dehydrogenation of n-heptane in the presence of Cr2O3/Al2O3 at 750 K primarily yields heptene (C7H14) along with hydrogen gas (H2).

### Final Answer
The products of the catalytic dehydrogenation of n-heptane in the presence of Cr2O3/Al2O3 at 750 K are heptene (C7H14) and hydrogen gas (H2).

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