Below are listed the major differences between compounds and mixtures . Which one is an incorrect pairing ?

Options

A. MIXTURE-Physical union,COMPOUND-Chemical union
B. MIXTURE-No new substances are formed ,COMPOUND-New substances are formed
C. MIXTURE-Can be separated by physical means ,COMPOUND-Can be separated by physical means
D. MIXTURE-Elements form no definite proportions ,COMPOUND-Elements form definite proportions

Explanation

To solve the question regarding the incorrect pairing between compounds and mixtures, we will analyze each statement provided in the question step by step.

### Step 1: Analyze the first pairing
**Pairing:** Mixture - Physical union; Compound - Chemical union
**Analysis:** This statement is correct. A mixture is formed by the physical combination of substances, while a compound is formed through a chemical reaction where elements combine in a specific ratio.
**Conclusion:** This is not the incorrect pairing.

### Step 2: Analyze the second pairing
**Pairing:** Mixture - No new substances are formed; Compound - New substances are formed
**Analysis:** This statement is also correct. In a mixture, the original substances retain their properties and no new substances are formed. In a compound, the elements react chemically to form a new substance with different properties.
**Conclusion:** This is not the incorrect pairing.

### Step 3: Analyze the third pairing
**Pairing:** Mixture - Can be separated by physical means; Compound - Can be separated by physical means
**Analysis:** This statement is incorrect. Mixtures can indeed be separated by physical means (e.g., filtration, distillation), but compounds cannot be separated by physical means; they require chemical methods to break down into their constituent elements.
**Conclusion:** This is the incorrect pairing.

### Step 4: Analyze the fourth pairing
**Pairing:** Mixture - Elements form no definite proportion; Compound - Elements form definite proportions
**Analysis:** This statement is correct. In a mixture, the components can be present in any proportion, while in a compound, the elements combine in a fixed ratio (e.g., water is always H2O).
**Conclusion:** This is not the incorrect pairing.

### Final Answer
The incorrect pairing is:
**Mixture - Can be separated by physical means; Compound - Can be separated by physical means.**

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