Dash Model

This is the dash structure for ethylene, C2H4.

The Bonds

The bond between carbon and carbon is absolutely covalent because any element bonded with itself is purely covalent. This is a nonpolar bond. To reassure this we can use an electronegativity table. Carbon's value is 2.2.

2.2 - 2.2 = 0 absolutely covalent bond

The bond between carbon and hydrogen is very covalent.

2.5 - 2.2 = 0.3 very covalent bond.

Polar vs. Nonpolar

Ethylene is a nonpolar molecule. This is because, unlike a polar molecule, it has an even distribution of electrical charges. No end of the molecule is more negatively or positively charged than another end. Also, there is more than one line of symmetry present which aided me in coming to this conclusion.

THE MOLECULE

This image shows a model of ethylene. There are bonds present off of the carbons to the four hydrogens. Also, there is a double bond present between the two carbons.

This is the same image except arrows were inserted to indicate the polarity of the bonds. Carbon's electronegativity value is 2.5 and hydrogen's is 2.2 The arrows were drawn towards the carbon because it possesses the higher charge. Also a positive sign was placed to show the charge of different ends of the molecule.

Intermolecular Forces of Attraction

The only force of attraction that could exist between ethylene and itself is London Dispersion Forces. Ethylene is a nonpolar molecule and thus the only force that it can feel is dispersion forces. All molecules experience this very weak attraction. It is caused by a temporary dipole that forms due to the rapid movement of electrons around atoms. It cannot experience a dipole-dipole attraction because it is nonpolar and there for does not have a positive and negative end. Also, it can not experience hydrogen bonding. This is because hydrogen only occurs between hydrogen and oxygen, nitrogen, or fluorine.