Calcium rods are used in nuclear reactors to slow down the neutrons taking part in the fission process

Answer

To determine whether the statement "Calcium rods are used in nuclear reactors to slow down the neutrons taking part in the fission process" is true or false, we can follow these steps:

### Step 1: Understand the Role of Neutrons in Nuclear Fission
In a nuclear reactor, neutrons play a crucial role in the fission process. When a nucleus of fissile material (like Uranium-235) absorbs a neutron, it becomes unstable and splits into two smaller nuclei, releasing energy and more neutrons.

**Hint:** Neutrons are essential for sustaining the fission chain reaction in nuclear reactors.

### Step 2: Identify the Purpose of Moderators
Moderators are materials used in nuclear reactors to slow down fast-moving neutrons. Slowing down neutrons increases the probability of them being absorbed by fissile material, thus sustaining the fission process. Common moderators include water (H2O), heavy water (D2O), and graphite.

**Hint:** Moderators are crucial for enhancing the efficiency of the fission process by slowing down neutrons.

### Step 3: Evaluate the Statement about Calcium Rods
The statement claims that calcium rods are used to slow down neutrons. However, calcium is not typically used as a moderator in nuclear reactors. Instead, materials like water and graphite are used for this purpose.

**Hint:** Check the common materials used in nuclear reactors for moderating neutrons.

### Step 4: Clarify the Use of Control Rods
Control rods, which can be made of materials like cadmium or boron, are used to absorb excess neutrons and control the rate of the fission reaction. This is different from the role of moderators.

**Hint:** Control rods absorb neutrons, while moderators slow them down.

### Step 5: Conclusion
Based on the information gathered, we can conclude that the statement is **false**. Calcium rods are not used to slow down neutrons in nuclear reactors; instead, materials like water and graphite serve this purpose.

**Final Answer:** The statement is **false**.