Which of the following statements about liquid nitrogen is true

Options

A. It is unreactive
B. It is used in cryosurgery
C. It does not decompose organic compounds
D. It is very stable

Explanation

To determine which statements about liquid nitrogen are true, we will analyze each statement provided and evaluate their accuracy based on known properties and applications of liquid nitrogen.

### Step 1: Evaluate the first statement - "Liquid nitrogen is unreactive."
- Liquid nitrogen (LN2) is known to be inert under normal conditions, but it can react with certain substances, especially when they are heated or in the presence of other reactive agents. Therefore, this statement is **false**.

**Hint:** Think about the conditions under which a substance can be considered reactive or unreactive.

### Step 2: Evaluate the second statement - "Liquid nitrogen is used in cryo-surgery."
- Cryo-surgery is a medical procedure that uses extreme cold to destroy abnormal or diseased tissue. Liquid nitrogen is commonly used in this application because of its low temperature. This statement is **true**.

**Hint:** Consider the applications of substances at very low temperatures in medical procedures.

### Step 3: Evaluate the third statement - "Liquid nitrogen does not decompose organic compounds."
- Liquid nitrogen can indeed interact with organic compounds, particularly when they are exposed to extreme cold. While it may not decompose them in the traditional sense, it can cause physical changes or reactions in certain conditions. Thus, this statement is **false**.

**Hint:** Reflect on how extreme temperatures can affect the stability and structure of organic compounds.

### Conclusion:
Based on the evaluations:
- The first statement is false.
- The second statement is true.
- The third statement is false.

Therefore, the true statement about liquid nitrogen is that it is used in cryo-surgery.

### Final Answer:
The correct statement about liquid nitrogen is: **It is used in cryo-surgery.**

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