HV Exit Exam • Set 6 Question 15 of 30

What is the density of Sulphur Hexafluoride (SF6) gas compared to ambient air?

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Direct Answer

Option D: It is approximately 5 times denser than air

SF6 has a molecular weight of 146.06 g/mol, making it approximately 5 times heavier (denser) than air (~29 g/mol). It tends to accumulate in low-lying spaces and bilges.

All Options

It is lighter than hydrogen

It is lighter than atmospheric air

It has identical density to air

It is approximately 5 times denser than air (Correct Answer)

Detailed Explanation & Context

SF6 has a molecular weight of 146.06 g/mol, making it approximately 5 times heavier (denser) than air (~29 g/mol). It tends to accumulate in low-lying spaces and bilges.

Relevant Framework: STCW 2010 Manila Amendments • DG Shipping E-Learning & Exit Exam Standards • High Voltage Safety Officer & Switchgear Operations (HV).

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