Select whether the statement is true or false . Gay-Lussac’s law of chemical combination is valid for all substances.

Answer

To determine whether the statement "Gay-Lussac’s law of chemical combination is valid for all substances" is true or false, we can follow these steps:

### Step 1: Understand Gay-Lussac's Law
Gay-Lussac's law states that the pressure of a gas is directly proportional to its absolute temperature when the volume is held constant. This law is specifically applicable to gases.

### Step 2: Identify the Scope of the Law
Since Gay-Lussac's law applies to gases, we need to recognize that it does not apply to liquids or solids. The behavior of gases under changing temperature and pressure conditions is different from that of liquids and solids.

### Step 3: Analyze the Statement
The statement claims that Gay-Lussac’s law is valid for all substances. Since we established that this law is only applicable to gaseous substances, the statement is incorrect.

### Conclusion
Therefore, the statement "Gay-Lussac’s law of chemical combination is valid for all substances" is **False**.

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