Nitrogen combines, with oxygen to form five gaseous oxides `N_(2)O, NO, N_(2)O_(4), NO_(2)`, and `N_(2)O_(5)` . This illustrates

Options

A. Gay-Lussac law
B. Law of constant composition
C. Law of multiple proportion
D. Avogadro's law

Explanation

To solve the question regarding the combination of nitrogen with oxygen to form various gaseous oxides, we can follow these steps:

### Step 1: Identify the Compounds Formed
The question states that nitrogen combines with oxygen to form five gaseous oxides:
- \( N_2O \)
- \( NO \)
- \( N_2O_4 \)
- \( NO_2 \)
- \( N_2O_5 \)

### Step 2: Understand the Concept of Chemical Combination
When two elements combine to form different compounds, the ratios in which they combine can vary. This is a fundamental concept in chemistry that relates to how elements interact and form compounds.

### Step 3: Recall the Relevant Laws of Chemical Combination
There are several laws that govern chemical combinations:
- **Law of Conservation of Mass**: Mass is conserved in a chemical reaction.
- **Law of Definite Proportions**: A chemical compound always contains its component elements in fixed ratio by mass.
- **Law of Multiple Proportions**: When two elements combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in a ratio of small whole numbers.

### Step 4: Apply the Law of Multiple Proportions
In this case, nitrogen and oxygen combine in different ratios to form different compounds. For example:
- \( N_2O \) has a different ratio of nitrogen to oxygen compared to \( N_2O_5 \).
- This illustrates the law of multiple proportions, as the same elements (nitrogen and oxygen) can combine in different ways to form different compounds.

### Step 5: Conclusion
Thus, the formation of these five gaseous oxides from nitrogen and oxygen illustrates the **Law of Multiple Proportions**.

### Final Answer
The correct answer is: **The law of multiple proportions**.

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