In a methane molecule (CH4) there are 4 single covalent bonds. In an octane molecule (C8H18) there are 25 single covalent bonds. How does the number of bonds affect the dispersion forces in samples of methane and octane? Which compound is a gas at room temperature? which is a liquid?
4 answers
Larger molecules are more polarizable; therefore, there is more interaction between molecules of octane due to instantaneous dipole-induced dipole forces (dispersion). For this reason, octane is a liquid and methane is a gas at room temperature.
Why does a pile of snow slowly shrink even on days when the temperature never rises above the freezing point of water?
Methane molecule ch4 covalent bond
More bonds mean more electrons to form temporary dipoles, which means greater dispersion forces. Methane is a gas; octane is a liquid.