Air Is 79% N₂ and 21% O₂ by Volume

question 1

Multiple Choice

Air is 79% N₂ and 21% O₂ by volume. Calculate the density of air at 1.0 atm, 25°C.

• A) 1.18 g/L
• B) 2.46 g/L
• C) 0.590 g/L
• D) 14.1 g/L
• E) none of these

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Definitions:

Glandular Epithelium

A type of epithelial tissue that forms the secreting portion of glands, either endocrine or exocrine.

Underlying Connective Tissue

The supportive tissue that lies beneath epithelial tissue, providing structural and nutritional support to epithelial cells.

Pseudostratified Columnar

Describes a type of epithelial tissue where cells of different heights appear to be in layers, but all cells are attached to the basement membrane.

Simple Squamous

A type of epithelial cell that is flat and thin, often found lining surfaces involved in passive diffusion, such as the alveoli in the lungs.