The monomer unit of silicon, a water repellant, acid resistantl,and heat resistant,polymer,is:

Options

A. `Si`
B. `SiO_(2)`
C. `R_(2)SiO`
D. None of these

Answer

To solve the question regarding the monomer unit of silicon that is water-repellent, acid-resistant, and heat-resistant, we can follow these steps:

### Step 1: Understand the question
The question asks for the monomer unit of a specific type of polymer that has properties such as being water-repellent, acid-resistant, and heat-resistant.

### Step 2: Identify the options
The options provided are:
1. Si
2. SiO2
3. R2SiO
4. None of these

### Step 3: Analyze the options
- **Si**: This represents silicon in its elemental form, which is not a polymer.
- **SiO2**: This is silicon dioxide, commonly known as quartz or sand, and is not a polymer.
- **R2SiO**: This represents a type of silicone polymer where "R" stands for organic groups (like methyl or ethyl). This structure is known for its water-repellent, acid-resistant, and heat-resistant properties.
- **None of these**: This option suggests that none of the above are correct.

### Step 4: Determine the correct answer
From the analysis, the option that represents the monomer unit of the polymer described in the question is **R2SiO**. This is because silicones, which are polymers made from this monomer, exhibit the desired properties.

### Final Answer
The correct answer is **R2SiO** (Option C).

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