30/4/2013 Week 3 Tuesday Period 3

A lot of research into the volume contraction tells me that you can possibly effect the measurement of volume contraction one or two ways; either by changing the temperature of the mixture components to affect the hydrogen bonding or by using different ratios of water to an alkanol (with the different ratios I can also modify it to use different types of alkanols as their chemical structure will have an effect on how strong there dipole-dipole forces are).

I have devised possible hypothesis to base this EEI on all under the topic of volume contraction.

Hypothesis 1:
The higher the ratio of water to ethanol (I've chosen the most basic alcohol to test) the larger the volume contraction will be.

The hydrogen bond is affected by temperature and pressure (http://en.wikipedia.org/wiki/Hydrogen_bond). Therefore by choosing a mixture ratio of water to ethanol that inhibits a large volume contraction I could then  base an EEI around how stable the volume contraction remains under temperature change. I would further have to research how temperature effects hydrogen bonding as hydrogen bonding is what causes the volume to contract when mixed.

Hypothesis 2:
The higher the temperature of the water and ethanol mixture the less stable the contraction will be and the volume contraction would be less.

Again I could test how volume contraction is affected by using different types of alkanols such as; ethanol, propanol, butanol etc.. but I will further develop the above hypotheses and make a choice on which one I will base the EEI on.

This diagram demonstrates how the water molecule is bonding to the ethanol. Here is the link where I found the image along with further information on hydrogen bonding with different alkanols. http://www.elmhurst.edu/~chm/vchembook/162othermolecules.html