An inhibitor is described as,

Options

A. a substance that slows down or stops a reaction
B. a substnace which inhibits the properties of a catalyst
C. a substance formed during the reaction and does not participate in the reaction
D. a substance which prevents formationn of products in a reaction being most reactive.

Answer

To answer the question "An inhibitor is described as," we need to analyze the properties and functions of inhibitors in chemical reactions. Here’s a step-by-step breakdown:

### Step 1: Definition of an Inhibitor
An inhibitor is a chemical substance that decreases the rate of a chemical reaction. It does not necessarily stop the reaction completely but slows it down.

**Hint:** Remember that inhibitors affect the speed of reactions rather than stopping them entirely.

### Step 2: Inhibitor vs. Catalyst
Inhibitors have properties that are opposite to those of catalysts. While a catalyst increases the rate of a reaction, an inhibitor decreases it. This means that if an inhibitor is present in a reaction that also has a catalyst, the inhibitor will inhibit the effectiveness of the catalyst.

**Hint:** Compare the roles of inhibitors and catalysts to understand their opposing effects on reaction rates.

### Step 3: Formation of Substances
Inhibitors do not produce any new substances during the reaction. They participate in the reaction by affecting the rate but are not consumed or formed as products.

**Hint:** Focus on the role of inhibitors in the reaction mechanism rather than their production.

### Step 4: Impact on Product Formation
While inhibitors slow down reactions, they do not prevent the formation of products entirely. Instead, they reduce the rate at which products are formed.

**Hint:** Consider how the presence of an inhibitor changes the speed of product formation rather than eliminating it.

### Conclusion
Based on the analysis:
- An inhibitor is a substance that decreases the rate of reaction.
- It inhibits the properties of a catalyst.
- It does not produce any substances during the reaction.
- It slows down the formation of products but does not stop it entirely.

### Final Statement
An inhibitor is described as a substance that decreases the rate of a reaction and inhibits the properties of a catalyst.

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