In an atom bomb, the energy is released because of the.

Options

A. chain reaction of neutrons and `""_(92)U^(235)`
B. chain reaction of neutrons and `""_(92)U^(238)`
C. chain reaction of neutrons and `""_(92)U^(240)`
D. chain reaction of neutrons and `""_(92)U^(236)`

Explanation

To solve the question regarding the energy release in an atom bomb, we can break it down into the following steps:

### Step 1: Understanding Nuclear Fission
In an atom bomb, energy is released through a process called nuclear fission. This is when a heavy nucleus, such as Uranium-235 (U-235), absorbs a neutron and becomes unstable.

**Hint:** Recall that nuclear fission involves the splitting of a heavy nucleus into smaller nuclei.

### Step 2: Neutron Absorption
When a U-235 nucleus captures a slow-moving neutron, it becomes U-236, which is highly unstable. This instability leads to the nucleus splitting into two smaller nuclei (daughter nuclei) and releasing additional neutrons.

**Hint:** Think about what happens when a neutron collides with a nucleus and how it affects the nucleus's stability.

### Step 3: Chain Reaction
The neutrons released from the fission of U-235 can go on to collide with other U-235 nuclei, causing them to undergo fission as well. This creates a chain reaction, where each fission event produces more neutrons, leading to further fission events.

**Hint:** Consider how one event can trigger multiple subsequent events in a chain reaction.

### Step 4: Energy Release
The fission process releases a tremendous amount of energy, primarily in the form of kinetic energy of the fission fragments and the kinetic energy of the released neutrons. This energy is what causes the explosion of the atom bomb.

**Hint:** Remember that the energy released in nuclear reactions is much greater than that released in chemical reactions.

### Step 5: Conclusion
In summary, the energy in an atom bomb is released due to the chain reaction of nuclear fission involving U-235, where the absorption of neutrons leads to the splitting of nuclei and the release of a large amount of energy.

**Final Answer:** In an atom bomb, the energy is released because of the chain reaction of nuclear fission involving U-235.