Which of these chemical substances is made up of atoms of more than one kind?

Options

A. Oxygen
B. Iodin
C. Water
D. Iron

Answer

To determine which chemical substance is made up of atoms of more than one kind, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the first option: Oxygen (O2)**
- Oxygen exists as a diatomic molecule, O2.
- In O2, there are 2 atoms, and both are Oxygen atoms.
- Since there is only one type of atom (Oxygen), this option does not meet the criteria.
- **Conclusion:** O2 is made up of only one kind of atom.

2. **Identify the second option: Iodine (I2)**
- Iodine also exists as a diatomic molecule, I2.
- In I2, there are 2 atoms, and both are Iodine atoms.
- Similar to Oxygen, there is only one type of atom (Iodine) present.
- **Conclusion:** I2 is made up of only one kind of atom.

3. **Identify the third option: Water (H2O)**
- The chemical formula for water is H2O.
- In H2O, there are 2 Hydrogen atoms and 1 Oxygen atom.
- Here, we have two different types of atoms: Hydrogen and Oxygen.
- **Conclusion:** H2O is made up of more than one kind of atom.

4. **Identify the fourth option: Iron (Fe)**
- Iron is a metal and is represented by the symbol Fe.
- Iron is an element, meaning it consists of only one type of atom (Iron).
- **Conclusion:** Fe is made up of only one kind of atom.

### Final Answer:
The chemical substance made up of atoms of more than one kind is **Water (H2O)**.

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