If an Atom X Has an Atomic Number of 18

question 8

Multiple Choice

If an atom X has an atomic number of 18, then:

• A) there are 18 protons.
• B) there are 9 protons and 9 electrons.
• C) there are 18 neutrons.
• D) there are 9 protons and 9 neutrons.
• E) it also has a mass number of 18.

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Definitions:

Evolutionary Diagram

A block diagram, cross section, or map that shows the history of an area as a series of steps, proceeding from the earliest stages to the most recent one.

Geologic Diagrams

Visual representations of the Earth's surface and subsurface used to understand and interpret geological features, processes, and history.

Geologic History

The record of Earth's physical history and the processes acting upon the planet, as deciphered from rocks, fossils, and other geological data.

Cenozoic

The Cenozoic era is the current geological era, beginning about 66 million years ago, characterized by the dominance of mammals, the formation of modern continents, and significant climatic changes.