Radioactive disintegration differs from a chemical change in being

Options

A. An exothermic change
B. A spontaneous process
C. A nuclear process
D. A unimolecular first-order reaction

Explanation

To answer the question "Radioactive disintegration differs from a chemical change in being," we need to analyze the characteristics of radioactive disintegration and compare them with those of chemical changes. Here's a step-by-step solution:

### Step 1: Understand Radioactive Disintegration
Radioactive disintegration refers to the process by which an unstable atomic nucleus loses energy by emitting radiation. This process can result in the transformation of one element into another and involves changes at the nuclear level.

### Step 2: Understand Chemical Changes
Chemical changes involve the rearrangement of atoms to form new substances. These changes occur through the breaking and forming of chemical bonds and typically involve interactions between electrons in the outer shells of atoms.

### Step 3: Compare Energy Changes
Both radioactive disintegration and chemical changes can release energy (exothermic) or absorb energy (endothermic). Therefore, energy change is not a distinguishing factor.

### Step 4: Spontaneity of Processes
Radioactive disintegration can occur spontaneously without any external influence, while some chemical reactions may require specific conditions or catalysts to proceed. However, there are also spontaneous chemical reactions, so this is not a unique characteristic.

### Step 5: Identify Nuclear Processes
Radioactive disintegration is a nuclear process, meaning it involves changes in the nucleus of an atom. In contrast, chemical changes do not involve the nucleus; they only involve the electrons surrounding the nucleus. This is a key differentiating factor.

### Step 6: Consider Reaction Order
Both radioactive disintegration and certain chemical reactions can be classified as first-order reactions. This means that this characteristic does not serve as a distinguishing factor either.

### Conclusion
The primary difference between radioactive disintegration and chemical changes is that radioactive disintegration is a nuclear process, while chemical changes do not involve nuclear reactions.

### Final Answer
Radioactive disintegration differs from a chemical change in being a nuclear process.

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