Question

Which one of the following statements related to bitumen is FALSE?

• A. Kinematic viscosity is a measure of resistance to the flow of molten bitumen under gravity.
• B. Softer grade bitumen possesses higher softening point than hard grade bitumen.
• C. Flash point of bitumen is the lowest temperature at which application of a test flame causes vapours of the bitumen to catch an instant fire in the form of flash under specified test conditions.
• D. Ductility test is carried out on bitumen to test its adhesive property and ability to stretch.

Hint:

Softer bitumen grades have lower softening points compared to harder bitumen grades, which are used in hotter climates to prevent deformation.

Answer 1

The Correct Option is B

Step 1: Evaluating statement (A): Kinematic viscosity is indeed a measure of the resistance to flow of molten bitumen under the influence of gravity. This statement is true. Step 2: Evaluating statement (B): Softer grade bitumen actually possesses a lower softening point compared to hard grade bitumen. Harder bitumen has a higher softening point to withstand high temperatures. Therefore, this statement is false. Step 3: Evaluating statement (C): The flash point of bitumen is defined correctly in the statement. It represents the temperature at which vapors of bitumen ignite momentarily when exposed to a test flame. This statement is true. Step 4: Evaluating statement (D): The ductility test measures the ability of bitumen to stretch and assess its adhesive properties. This statement is true. Conclusion: Since statement (B) is incorrect, the correct answer is option (B).