X-Ray Diffraction: Certain Planes of a Crystal of Halite Have

question 82

Multiple Choice

X-ray diffraction: Certain planes of a crystal of halite have a spacing of 0.399 nm. The crystal is irradiated by a beam of X-rays. First order constructive interference occurs when the beam makes an angle of 20° with the planes. What is the wavelength of the X-rays?

• A) 0.14 nm
• B) 0.17 nm
• C) 0.21 nm
• D) 0.24 nm
• E) 0.27 nm

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Definitions:

Energy Expenditure

The total amount of energy used by the body per day, encompassing basal metabolic rate, physical activity, and the energy used in digesting and metabolizing food.

Plasma Membrane

The semipermeable membrane surrounding the cytoplasm of a cell, responsible for controlling the passage of substances in and out.

Bilayer

A bilayer typically refers to a double layer of closely packed atoms or molecules, the most common example being the lipid bilayer of cell membranes that forms the cell's outer boundary.

Phospholipids

A class of lipids that are a major component of all cell membranes as they can form lipid bilayers.