Physical and Chemical Properties of Helium

• Atomic Number: 2
• Atomic Symbol: He
• Atomic Weight: 4.0026
• Phase at Room Temperature: Gas
• Boiling Point: -268.9°C
• Melting Point: -272.2°C
• Density: 0.1786 grams/liter
• State of Matter: Noble Gas

Uses of Helium

Helium has several important uses, including:

• As a coolant for nuclear reactors and in cryogenics
• In the production of silicon wafers and fiber optics
• In gas chromatography and as a carrier gas for various analytical instruments
• In gas mixtures for deep-sea diving and medical applications
• In filling balloons and airships due to its low density

Study Guide

When studying helium, it's important to understand its physical and chemical properties, as well as its uses. Here are some key points to focus on:

1. Describe the atomic structure of helium, including the number of protons, neutrons, and electrons.
2. Explain why helium is classified as a noble gas and its significance in the periodic table.
3. Discuss the unique physical properties of helium, such as its low boiling and melting points.
4. Explore the various industrial and scientific applications of helium, including its use as a coolant and in gas chromatography.
5. Investigate the role of helium in medical and recreational settings, such as in diving and balloon filling.

Understanding these aspects of helium will provide a comprehensive grasp of its significance in various fields of science and industry.