A Sample of He Gas (2

question 47

Multiple Choice

A sample of He gas (2.0 mmol) effused through a pinhole in 53 s.The same amount of an unknown gas,under the same conditions,effused through the pinhole in 248 s.The molecular mass of the unknown gas is ________ g/mol.

• A)0.19
• B)5.5
• C)88
• D)19
• E)350

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Definitions:

Epidermis

The outermost layer of the skin that provides a waterproof barrier and creates skin tone.

Oral Care

The practice of keeping the mouth, teeth, and gums clean and healthy to prevent disease, including regular brushing and dental check-ups.

Dental Visits

Appointments with a dentist for the examination, cleaning, and treatment of teeth and gum conditions to maintain oral health.

Preschool Child

A child who is in the age group that precedes formal schooling, typically aged between 3 to 5 years.