Among the radioactive elements, which is a liquid element?

Explanation

To determine which radioactive element is a liquid at room temperature, we can follow these steps:

### Step 1: Identify Radioactive Elements
First, we need to list some of the known radioactive elements. These include Uranium (U), Thorium (Th), Radium (Ra), Francium (Fr), and others.

### Step 2: Check Physical States of Radioactive Elements
Next, we need to check the physical states (solid, liquid, gas) of these radioactive elements at room temperature (approximately 20-25 degrees Celsius).

- Uranium: Solid
- Thorium: Solid
- Radium: Solid
- Francium: Liquid (melting point around 27°C)

### Step 3: Identify the Liquid Element
From our list, we can see that Francium is the only radioactive element that is a liquid at room temperature.

### Conclusion
Thus, among the radioactive elements, **Francium (Fr)** is the liquid element.

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