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Detergents Make Water Wetter




To get things clean, water must penetrate deeply into the fabric.  A glance at the water beads on your umbrella shows that water isn’t particularly good at wetting things.  The problem is it has a high surface tension, which makes water behave as if it had a thin skin on it.  That’s why insects can walk on water.

Washing powders and detergents work to make water wetter by lowering its surface tension.  This enables the water to carry detergent molecules deep into the fibres, where they can come into close contact with the dirt.

Detergent molecules are like little tadpoles.  The heads are attracted to the water molecules by a small electric charge, while the tails, which are chemically very similar to grease, are repelled by water molecules.  So the tail of the detergent molecule attaches itself to the grease.  With their heads attracted to water, and their tails embedded in the grease, the detergent molecules hold the water and dirt together, until they float away as the clothes are agitated.

Washing powders may involve other things besides detergent.  These include bleach, enzymes to break down protein stains like blood and perspiration, and bluing agents, which make the laundry appear whiter.  Bluish dyes absorb some of the reflected yellow light.  This brings it more into balance with the blue light, so that the material appears whiter to the eye.

So next time you wear a white top, spare a thought for the hard working molecules that drag out the dirt.


 by Ron Hughes

Getting things clean occupies a significant amount of time and energy.  Kitchen utensils, the clothing we wear, the buildings we use, and our bodies all have the tendency to accumulate “dirt.”  

Keeping the various aspects of our personal environment clean is not the only cleaning challenge we have to deal with.  The moral universe presents a whole series of obstacles all of its own.  

When it comes to setting the mark for human moral behaviour, we will always be in trouble if we use our own shifting, self-interested frame of reference to establish the rule.  We live in an orderly physical universe.  Modern science got a huge boost from scientists working to discover the laws of nature embedded by God in creation.

In the spiritual realm, we can get great benefit from investigating the laws which govern it.  Spiritual laws and principles are rooted in God Himself.  God intends for us to be reflectors of his likeness to those around us.  To do that, we must be like Him – to act as He acts – to speak His words – even to think His thoughts.

While some have a rather cloudy, soft-focus understanding of God, the fact is that He has very specific characteristics and qualities.  The really amazing thing is that these are all complementary.  They are never in opposition to each other.  Even if you were to take two seemingly contradictory ideas like “God is just” and “God is merciful” you would find that God is able to blend those perfectly.  This is not a matter of being just some of the time and merciful some of the time, but always just and always merciful.

How can this be?  The cross gives the answer.  When Jesus (the Son of God and Son of Man) died on the cross, He met the demands of God’s justice.  And because justice had been served, God’s mercy can be demonstrated to all those who accept that the death of the Lord Jesus Christ was, in effect, their own death.  And this is what allows us to be spiritually clean.


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