Crude oil may contain hundreds of different types of hydrocarbons. Some examples include:
- Butane [tex]$\left( C_4 H_{10} \right)$[/tex]
- Dodecane [tex]$\left( C_{12} H_{26} \right)$[/tex]
- Octane [tex]$\left( C_8 H_{18} \right)$[/tex]
- Benzene [tex]$\left( C_6 H_6 \right)$[/tex]

Many common fuels, such as gasoline and kerosene, are combinations of these substances or others. When these fuels burn, they combine with oxygen [tex]$\left( O_2 \right)$[/tex] to produce carbon dioxide [tex]$\left( CO_2 \right)$[/tex] and water [tex]$\left( H_2O \right)$[/tex].

Identify each of the highlighted materials as an element, a compound, or a mixture, and explain your reasoning.
[tex]$\square$[/tex]



Answer :

Certainly! Let's identify and categorize each substance mentioned in the question.

1. Butane (C₄H₁₀):
- Category: Compound
- Reasoning: Butane is a substance made up of carbon (C) and hydrogen (H) atoms bonded together in a specific ratio (4 carbon atoms to 10 hydrogen atoms). It has a definite chemical formula, indicating that it is a compound.

2. Dodecane (C₁₂H₂₆):
- Category: Compound
- Reasoning: Dodecane consists of carbon (C) and hydrogen (H) atoms combined in a fixed ratio (12 carbon atoms to 26 hydrogen atoms). This fixed composition and chemical formula classify dodecane as a compound.

3. Octane (C₈H₁₈):
- Category: Compound
- Reasoning: Octane is made up of carbon (C) and hydrogen (H) atoms in a specific ratio (8 carbon atoms to 18 hydrogen atoms). The presence of a definite chemical formula makes it a compound.

4. Benzene (C₆H₆):
- Category: Compound
- Reasoning: Benzene consists of carbon (C) and hydrogen (H) atoms in a 1:1 ratio (6 carbon atoms to 6 hydrogen atoms). The specific ratio and chemical formula of benzene qualify it as a compound.

5. Oxygen (O₂):
- Category: Element
- Reasoning: Oxygen (O₂) is made entirely of oxygen atoms. Since it consists of only one type of element (oxygen), it is classified as an element. In its molecular form (O₂), it comprises two oxygen atoms bonded together, but they are still the same element.

6. Carbon Dioxide (CO₂):
- Category: Compound
- Reasoning: Carbon dioxide is comprised of carbon (C) and oxygen (O) atoms in a fixed ratio (one carbon atom to two oxygen atoms). The definite ratio and chemical formula CO₂ mean that it is a compound.

7. Water (H₂O):
- Category: Compound
- Reasoning: Water consists of hydrogen (H) and oxygen (O) atoms in a fixed ratio (two hydrogen atoms to one oxygen atom). Its specific composition and chemical formula H₂O classify it as a compound.

8. Gasoline / Kerosene:
- Category: Mixture
- Reasoning: Gasoline and kerosene are not singular substances but rather combinations of many different hydrocarbons and other substances. They do not have a fixed composition or formula, which means they are mixtures.

In summary, the categorization of the substances is as follows:
- Element: Oxygen (O₂)
- Compound: Butane (C₄H₁₀), Dodecane (C₁₂H₂₆), Octane (C₈H₁₈), Benzene (C₆H₆), Carbon Dioxide (CO₂), Water (H₂O)
- Mixture: Gasoline, Kerosene

I hope this detailed explanation helps in understanding the classification of each substance!