What Is the Most Abundant Metallic Element in the Earth's

question 12

Multiple Choice

What is the most abundant metallic element in the earth's crust?

• A) iron
• B) cobalt
• C) aluminum
• D) gallium
• E) none of these

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Definitions:

Neurotransmitters

Chemicals that transmit signals across a synapse from one neuron to another in the nervous system.

Synapse

The junction between two neurons, where nerve impulses are transmitted from one to the other.

Sodium

A chemical element, symbol Na, that is a highly reactive metal and an essential mineral for living organisms.

Potassium

A chemical element with symbol K and atomic number 19, essential for various bodily functions including neural activity and muscle contraction.