Which one disappeared from earliest atmosphere during its conversion to primary atmosphere?

Options

A. Atomic state of gases
B. Oxygen
C. Ammonia
D. Both A and B

Answer

To solve the question "Which one disappeared from the earliest atmosphere during its conversion to primary atmosphere?", we can follow these steps:

### Step 1: Understand the Composition of the Earliest Atmosphere
The earliest atmosphere of Earth, formed around 4.6 billion years ago, was primarily composed of hot gases and solids. It did not contain free oxygen.

### Step 2: Identify the Gases Present
In the earliest atmosphere, various gases were present, including hydrogen, methane, ammonia, and water vapor. However, oxygen was notably absent.

### Step 3: Determine Which Gas Disappeared
As the Earth evolved, certain gases began to disappear from the atmosphere. Among these, ammonia (NH3) is known to have been one of the gases that diminished significantly during the transition from the earliest atmosphere to the primary atmosphere.

### Step 4: Conclusion
Based on the information gathered, the gas that disappeared from the earliest atmosphere during its conversion to the primary atmosphere is ammonia.

### Final Answer
The answer is ammonia (option number 3).

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