How Many Elements Are There in Period 2

question 70

Multiple Choice

How many elements are there in period 2?

• A) 2
• B) 6
• C) 8
• D) 18

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Definitions:

Aortic Valve

One of the four heart valves that controls blood flow from the heart into the aorta, the body's main artery.

Mitral Valve

A valve in the heart that lies between the left atrium and left ventricle, ensuring unidirectional blood flow through the heart.

Chest Tube

is a medical device inserted into the pleural space to remove air, fluids, or pus, often used in treating conditions like pneumothorax or pleural effusion.

Bubbling

The production of bubbles in a liquid caused by processes such as boiling, fermentation, or chemical reactions.