A fellow student say , " All substance experience London disperison forces of attraction between particle." Is this etatement true? Explain your answer
Yes, it is true. Here is a site to help you identify the reason.
http://www.chem.purdue.edu/gchelp/liquids/disperse.html
The London dispersion force is the weakest intermolecular force. The London dispersion force is a temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make the atoms form temporary dipoles. This force is sometimes called an induced dipole-induced dipole attraction. London forces are the attractive forces that cause nonpolar substances to condense to liquids and to freeze into solids when the temperature is lowered sufficiently.
Because of the constant motion of the electrons, an atom or molecule can develop a temporary (instantaneous) dipole when its electrons are distributed unsymmetrically about the nucleus.
That sounds ok BUT you are guilty of plagiarism if you don't put it in your own words. Here is a definition of plagiarism.
http://www.google.com/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=65O&ei=r-DrSeerLJSMtgeQ5rTFBQ&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=define%3Aplagiarism&spell=1
ok i understand but i have another question
OK but make it a new post at the top of the board.
To determine if the statement is true, we need to understand what London dispersion forces are and how they relate to substances.
London dispersion forces, also known as van der Waals forces, are weak intermolecular forces that exist between all particles, including atoms, molecules, or ions. These forces arise due to temporary fluctuations in electron distribution, which can induce dipole moments in neighboring particles.
While the statement suggests that all substances experience London dispersion forces, this is not entirely accurate. London dispersion forces are present in nonpolar substances, such as noble gases (e.g., helium, neon) and hydrocarbons (e.g., methane, hexane), where there is no significant permanent dipole moment. These forces are more pronounced in larger atoms or molecules due to their larger electron clouds, leading to more fluctuations and stronger dispersion forces.
However, London dispersion forces do not play a significant role in substances with polar bonds or molecules that have a permanent dipole moment. In these substances, other intermolecular forces such as dipole-dipole interactions and hydrogen bonding dominate.
Therefore, the statement is not entirely true. While all substances do experience some form of intermolecular forces, London dispersion forces are specific to nonpolar substances, whereas other types of forces operate in polar substances.