A combustible substance is usually made of ____, which are compounds of carbon and hydrogen.

Options

A. Halogens
B. Hydrocarbons
C. Alcohol
D. Esters

Answer

To answer the question "A combustible substance is usually made of ____, which are compounds of carbon and hydrogen," we need to identify the correct term that describes substances made up of carbon and hydrogen that can combust.

### Step-by-Step Solution:

1. **Understanding Combustible Substances**:
- A combustible substance is one that can burn in the presence of oxygen to produce heat and light.
- This means that the substance must contain elements that can react with oxygen.

**Hint**: Think about what happens when materials burn. What do they need to react with?

2. **Identifying the Components**:
- The question specifies that these substances are compounds of carbon and hydrogen.
- Compounds made up of only carbon and hydrogen are known as hydrocarbons.

**Hint**: Recall the basic definition of hydrocarbons. What elements are they composed of?

3. **Confirming the Correct Term**:
- Hydrocarbons can be found in many fuels, such as gasoline, natural gas, and propane.
- When hydrocarbons combust, they produce carbon dioxide and water, along with heat and light.

**Hint**: Consider common fuels that are used for burning. What do they primarily consist of?

4. **Choosing the Correct Answer**:
- The answer to the question is "hydrocarbons," as they are the compounds made of carbon and hydrogen that are typically combustible.

**Hint**: Look for the term that directly refers to compounds made of carbon and hydrogen.

### Final Answer:
A combustible substance is usually made of **hydrocarbons**, which are compounds of carbon and hydrogen.