Carbogin is

Options

A. pure form of carbon
B. mixture of CO and `CO_2`
C. `COCl_2`
D. mixture of `O_2 and CO_2`

Explanation

**Step-by-Step Solution:**

1. **Understanding Carbogen**: Carbogen is a specific mixture that consists of two gases: Carbon Dioxide (CO2) and Oxygen (O2).

2. **Composition of Carbogen**: The mixture is composed of 70% Carbon Dioxide by mass and 30% Oxygen. This ratio is crucial in defining what Carbogen is.

3. **Historical Context**: Carbogen is also referred to as Madiuna's mixture, named after the scientist who discovered it.

4. **Effects of Inhalation**: When inhaled, Carbogen can lead to suffocation. This is because the high concentration of Carbon Dioxide can create a situation where there is a lack of Oxygen, leading to symptoms such as increased heart rate and breathing rate.

5. **Identifying the Correct Answer**: Given the options provided:
- 1. Pure form of Carbon
- 2. Mixture of CO and CO2
- 3. CO-CO2
- 4. Mixture of Oxygen and CO2

The correct answer is option 4, which states that Carbogen is a mixture of Oxygen and Carbon Dioxide.

**Final Answer**: Carbogen is a mixture of Oxygen and Carbon Dioxide.

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