I am a gas. The following descriptions are made about me. What am I?
I am the simplest hydrocarbon.
I am the main constituent of natural gas found alongwith petroleum.
When I burn in an insufficient supply of air (oxygen), I form carbon monoxide and water.
I can be prepared in laboratory by heating a mixture of sodium acetate `(CH_3COONa)` and soda-lime.

Explanation

To solve the question, we need to analyze the clues provided about the gas in question. Let's break it down step by step:

### Step 1: Identify the simplest hydrocarbon
The first clue states, "I am the simplest hydrocarbon."
- Hydrocarbons are compounds made of hydrogen and carbon. The simplest hydrocarbon is methane, which has the chemical formula CH₄.

**Hint:** Think about the structure of hydrocarbons and which one has the least number of carbon and hydrogen atoms.

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