ANS:C - Viscosity

The parameter used for grading paraffin waxes is typically the melting point. Here’s why: Melting Point: Paraffin waxes are graded based on their melting points, which directly influence their application suitability. Higher melting point waxes are often used in applications requiring higher temperature stability, such as candle making and coatings. Lower melting point waxes are used in applications where flexibility and lower temperature stability are desired, such as in packaging and certain industrial processes. The other parameters mentioned:

• Specific Gravity: While specific gravity can be measured for paraffin waxes, it is not typically used as a primary grading parameter. Specific gravity can indicate density and purity but does not directly determine the wax's grade.
• Viscosity: Viscosity can vary depending on the temperature and molecular weight of the wax, but it is not a primary grading parameter for paraffin waxes.
• Penetration Number: Penetration number is more commonly used to measure the hardness or consistency of materials like greases and bitumen, not paraffin waxes.