Which of the following is correct for a carbon family?

Options

A. Tin mainly occurs as Cassiterite , `SnO_(2)`
B. Silicon is the third most abundant element on earth's crust
C. Only two isotopes of carbon are present `C^(12)` and `C^(13)`
D. Germanium is most abundant than other members of carbon family

Answer

To solve the question regarding the carbon family and identify the correct statement, let's analyze each option step by step.

### Step 1: Analyze Option 1
**Statement**: Tin mainly occurs as cassiterite SnO2.
**Analysis**: This statement is correct. Cassiterite (SnO2) is indeed the principal ore of tin. Therefore, this option is valid.

### Step 2: Analyze Option 2
**Statement**: Silicon is the third most abundant element in the Earth's crust.
**Analysis**: This statement is incorrect. Silicon is actually the second most abundant element in the Earth's crust, following oxygen. Thus, this option is not valid.

### Step 3: Analyze Option 3
**Statement**: Only two isotopes of carbon are present: C12 and C13.
**Analysis**: This statement is also incorrect. Carbon has three naturally occurring isotopes: C12, C13, and C14. Therefore, this option is not valid.

### Step 4: Analyze Option 4
**Statement**: Germanium is more abundant than other members of the carbon family.
**Analysis**: This statement is incorrect. Silicon is the most abundant member of the carbon family, not germanium. Therefore, this option is not valid.

### Conclusion
After analyzing all the options, the only correct statement is from Option 1: "Tin mainly occurs as cassiterite SnO2."

### Final Answer
The correct option is **1**.

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