Melting Snow and Ice

Posted by PITHOCRATES - February 5th, 2014

Technology 101

When Temperatures fall below Freezing Liquid Water turns into Solid Water

You know what the best thing about water is?  You don’t have to shovel it.  Well, that, and its life-giving properties.  Let’s face it.  We couldn’t survive without the stuff.  We couldn’t grow food.  We even couldn’t live without drinking water.  So perhaps its life-giving properties is the best thing about water.  But a close second would be that thing about not having to shovel it.

When it rains water soaks into our green areas.  It runs off driveways and sidewalks into green areas.  And into streets.  Where it runs off into a storm drainage system.  Which takes it to a river or lake.  The rain lets our gardens grow.  And any excess water conveniently just goes away.  We may have a puddle or two to slosh through.  But even those go away without us having to do anything.  Water is nice that way.  As long as the temperature is above its freezing point.

When the temperature falls below the freezing point of water bad things start to happen.  Liquid water turns into solid water.  And hangs around for awhile.  Accumulating.  On our driveways, sidewalks, porches and roads.  It’s pretty much everywhere we don’t want it to be.  Making it difficult to walk.  And drive.  We slip and fall a lot in it.  The sun may melt it a little during the day.  Creating puddles of water where the snow once was. But when the sun sets those puddles freeze.  And become even more slippery.  Making solid water more dangerous than liquid water.  So a big part of making it through winters in northern climes, then, is transforming solid water back into the liquid form.

Even though Bourbon melts Ice Cubes Bourbon would be a Poor Choice to melt Snow and Ice

All material can be in three different stages.  It can be a solid.  A liquid.  Or a gas.  What determines the phase of this material depends on a couple of things.  Mostly temperature and pressure.  And the chemical properties of the material.  At ambient temperature and pressure material typically exists stably in one phase.  Water, for example, is stable in the liquid phase on an 80-degree summer day.  Allowing us to swim in it.  While on a freezing February day it is stable in the solid phase.  Which is why we hold the Winter Olympics in February.  The cold temperatures give us the best solid water conditions.

If we raise the temperature of water we can turn it from a liquid to a gas.  We could also do this by lowering the ambient air pressure.  Such as putting it into a vacuum.  For a liquid remains a liquid as long as the vapor pressure (the tendency for particles to escape from the liquid they’re in) of the liquid is less than the ambient air pressure.  If we lower the ambient air pressure below the vapor pressure of the liquid we can lower the boiling point of that liquid.  This is why different liquids have different boiling points.  They have different vapor pressures.  Oxygen has a very high vapor pressure and requires a high pressure and cold temperature to keep oxygen in a liquid phase.

When we take ice cubes out of the freezer and add them to a glass of bourbon they melt.  Because the ambient temperature outside of the freezer is above the freezing point of water.  So the solid water changes its phase from solid to liquid.  It would follow, then, that pouring bourbon on snow and ice would help melt it.  Of course we don’t do that.  For wasting bourbon like that would be criminal.  Not to mention costly.  Even if you used the cheap stuff.  Making bourbon a poor choice for melting snow and ice.

Salt dissolves into a Brine Solution that lowers the Melting Point of Snow and Ice

We see that a material will change its phase at different temperatures and pressures.  Which is good to know.  But it doesn’t help us to melt snow and ice during winter.  For we can’t lower the atmospheric air pressure to lower the boiling and melting points of water.  And we can’t raise the ambient temperature above the melting point of water.  If we could our winters would probably be a lot more comfortable than they are now.  So because when we can’t change the air pressure or temperature of the ambient environment the snow and ice is in we do something else.  We use chemistry to lower the melting point of snow and ice.  And the most common chemical we use is salt.

To melt snow and ice salt needs heat and moisture.  The moisture comes from the snow and ice.  Or from the humidity in the air.  The heat comes from the warmth of the earth or air.  Heated by the sun.  It also comes from the friction between tires and the road.  When salt comes into contract with water and heat it dissolves into a brine solution.  And this brine solution has a much lower melting point than water.  Which in turn lowers the melting point of the snow and ice it comes into contact with.  Allowing it to be in the liquid phase at temperatures below freezing temperatures.  Melting that snow and ice so it can run off like rain water.

The warmer it is when it snows the quicker salt will melt that snow.  While the colder it is the longer it takes to melt.  If it gets too cold (around 15 degrees Fahrenheit) salt proves to be ineffective.  In temperatures below 15 degrees Fahrenheit other chemicals work better.  Such as calcium chloride.  But calcium chloride is more costly than sodium chloride (salt).  Ambient temperatures, time of day, sunny or cloudy, wind, etc., all determine the chemical to use.  And the amount of chemical to use.  They consider all of these factors (and more) before sending those ‘salt’ trucks out on the roads.  Allowing us to drive in the worst of winters just as we drive in the best of summers.  It may take more time.  And there may be a little more cussing.  But we still go to work, take our kids to school, go shopping, etc., when it snows.  Thanks to chemicals.  Chemistry.  And the people that put those chemicals and that chemistry to work.

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Mayor Bloomberg says Unhidden Cigarettes in Retail Stores encourage People to Start Smoking

Posted by PITHOCRATES - March 24th, 2013

Week in Review

New York City mayor Michael Bloomberg knows what’s best for New Yorkers.  Lucky for New Yorkers that they have Mayor Bloomberg to be their parent.  For apparently, without him, New Yorkers would be just too stupid for their own good (see New York mayor wants to ban stores from displaying cigarettes by Jonathan Allen posted 3/18/2013 on Reuters).

New York Mayor Michael Bloomberg on Monday proposed requiring that cigarettes be hidden from view in retail stores as a means to reduce smoking in what he said would be the first law of its kind in the United States…

Bloomberg, a former smoker, is accustomed to industry opposition from previous measures to improve the health of New Yorkers, including bans on smoking in most offices, restaurants, bars, parks and on beaches.

Bloomberg has also taken steps to curtail the use of trans fats and salt in the city’s restaurants. Last week a court unexpectedly struck down his attempt to limit the size of sugary drinks, in part because it did not go through the City Council. The city is appealing that ruling.

“These laws would protect New Yorkers, especially young and impressionable New Yorkers, from pricing, discounts and exposure to in-store displays that promote tobacco products,” Bloomberg told a news conference at a city hospital.

“Such displays suggest that smoking is a normal activity and they invite young people to experiment with tobacco. This is not a normal activity,” he said…

The proposal would also increase penalties on stores that illegally resell cigarettes smuggled in from states with lower tobacco taxes, which Bloomberg said cost the city $30 million in lost tax revenue every year.

Over the last 18 months, inspectors visiting 1,800 cigarette retailers found 46 percent were selling untaxed or unstamped tobacco products, city officials said. New York City cigarettes are the most expensive in the nation at around $12 or $13 a pack after federal, state and city taxes.

Cigarettes are a funny beast.  People like Mayor Bloomberg hate them and want to make it hard for people to smoke.  But he sure loves taxing them.  And when they find cheaper out-of-state cigarettes in stores what is his concern?  That these cheaper cigarettes will make it easier for poor people to smoke?  No.  It is the lost tax revenue to the city that these poor people aren’t paying.

People aren’t smoking because they see cigarettes for sale and say, “Hmmm, smoking looks irresistibly delightful.  I must try it.”  Kids smoke because their heroes in music, television and Hollywood smoke. They look cool smoking and these kids want to look cool like them.  And grown up.  For smoking is an acquired taste.  You have to work at it before you can stand the discomfort of smoking.  But kids do it.  Because they want to look older than they are.  And cool.  Like Jimmy Page, Eddie Van Halen, Slash, etc., look on stage with a cigarette hanging out of their mouth as they play a low-slung guitar.  That gets them the ladies.  Like the suave movie hero that gets the ladies and ends up in bed with them.  Who both enjoy a satisfying after-sex smoke.  To be cool like womanizing Don Draper.  Who starts his day with a bourbon and a smoke.  And the cool and liberated women who work with him in the Sixties that smoke.  This is why kids start smoking.  To be like the people they want to be like.  Not because they can see cigarettes for sale.

So smoking is not a ‘normal’ activity.  Well, we don’t need smoking to sustain the human race.  For it serves no necessary biological function.  So, yes, smoking is not normal.  But neither is recreational sex.  Or male-to-male sexual contact.  Which provides no biological function whatsoever.  So one would assume Mayor Bloomberg finds male-to-male sexual contact not a normal activity.  Which can result in AIDS.  According to the CDC there were approximately 16,694 adults and adolescent-men who contracted AIDS in 2011 from male-to-male sexual contact.  In the previous year AIDS claimed 15,529 lives.  Is the mayor going to place restrictions on these activities, too?  After all, he has gone after cigarettes, trans fats, salt, sugary drinks.  What’s to stop him from entering the bedroom.  After all, it’s for New Yorkers’ own good.

Now there are those on the Left who support regulating Americans in their personal life.  Because they think average Americans may not be smart enough to know better.  But where does it end?  Something to think about now that the government will be picking up the tab for our health care thanks to Obamacare.  And we will have to do pretty much whatever they tell us to do if we want some of their health care services.  And to cut costs they may try to ban certain unhealthy lifestyle choices.  From smoking.  To excessive sexual activity that can result in sexually transmitted diseases.  After all they’re banning assault rifles that claimed 323 lives in 2011.  Why wouldn’t they try to ban something that kills more people.  Like male-to-male sexual contact.

When you allow the state to ban lifestyle choices it can start with smoking and sugary drinks.  But it can end with activity behind the bedroom door.  Such as the Left is always accusing the Right of wanting to do.  But it isn’t the Right trying to micromanage our private life.  All the hostility to cigarettes and the foods we enjoy is primarily from the Left.  From those in the nanny state.  So it’s just a matter of time before the Left starts regulating our sexual lives.  Which they will claim they have the right to do.  As Obamacare gives them that right.  Because the state will now be paying for the consequences of our lifestyle choices.

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