Here are the essential concepts you must grasp in order to answer the question correctly.
Intermolecular Forces
Intermolecular forces are the attractive forces between molecules that influence physical properties such as boiling and melting points. These forces include hydrogen bonding, dipole-dipole interactions, and London dispersion forces. Understanding these forces is crucial for predicting how substances behave in different states and conditions.
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Noble Gases
Helium (He) is a noble gas, characterized by a complete valence shell, which makes it chemically inert. Noble gases primarily exhibit London dispersion forces, which are weak and arise from temporary dipoles created when electron distributions fluctuate. This results in very low boiling and melting points for noble gases compared to other elements.
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Phase Changes
Phase changes refer to the transitions between solid, liquid, and gas states of matter, which are influenced by intermolecular forces. The strength of these forces determines the energy required for a substance to change phases. For helium, the weak London dispersion forces mean it remains a gas at very low temperatures, only condensing under extreme conditions.
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