The Ratio of the Numbers of Neutrons to Protons in the Nucleus

question 12

Multiple Choice

The ratio of the numbers of neutrons to protons in the nucleus of naturally occurring isotopes tends to vary with atomic number in what manner?

• A)increases with greater atomic number
• B)decreases with greater atomic number
• C)is maximum for atomic number = 60
• D)remains constant for entire range of atomic numbers

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Definitions:

Diethylstilbestrol

A synthetic estrogen that was prescribed between the 1940s and 1971 to prevent pregnancy complications, later found to cause cancer and other significant health issues.

Teratogens

Agents or factors that can cause malformation or defects in the developing embryo or fetus.

Blastocyst

An early stage of embryonic development characterized by a fluid-filled structure that, after implantation in the uterus, develops into the embryo and placenta.

Endoderm

The innermost layer of cells or tissue of an embryo in early development, which gives rise to the lining of the digestive and respiratory systems.