When `100 g` of ethylene polymerises entirely to polythene, the weight of polyethene formed as per the equation `nCH_(2)=CH_(2) rarr (CH_(2)-CH_(2))n` is :

Options

A. `(n//2)g`
B. `100g`
C. `(100//n)g`
D. `100n g`

Answer

To solve the problem of determining the weight of polythene formed when 100 g of ethylene polymerizes, we can follow these steps:

### Step 1: Understand the Reaction
The reaction given is:
\[ n \text{CH}_2=\text{CH}_2 \rightarrow (\text{CH}_2-\text{CH}_2)_n \]
This indicates that 'n' moles of ethylene (CH₂=CH₂) polymerize to form polythene (CH₂-CH₂)n.

### Step 2: Analyze the Mass Conservation
In a chemical reaction, mass is conserved. This means that the total mass of the reactants will equal the total mass of the products. Here, we are starting with 100 g of ethylene.

### Step 3: Apply the Conservation of Mass
Since the entire 100 g of ethylene is converted into polythene without any loss or gain of mass (no by-products or side reactions), the mass of polythene formed will also be 100 g.

### Step 4: Conclusion
Therefore, the weight of polythene formed when 100 g of ethylene polymerizes entirely is:
\[ \text{Weight of polythene} = 100 \text{ g} \]

### Final Answer
The weight of polythene formed is **100 g**.

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