MOTHBALLS ARE BAD FOR YOUR HEALTH - Mothballs are typically made with either naphthalene or 1,4-dichlorobenzene, both of which are toxic to humans and pets. While these chemicals are solid at room temperature, and can be molded into mothballs, they will gradually change to gas over time, emitting fumes into the air (and that’s where the mothball odor comes from). Both naphthalene and 1,4-dichlorobenzene can cause headaches, nausea, eye and nose irritation, and coughing. Naphthalene is also a possible carcinogen, and can cause more serious issues like hemolytic anemia. The compounds inside of a mothball sublimate – meaning they go straight from solid to gas – by design. So yes, the fumes that can make you ill are intentionally released; that’s how mothballs are supposed to work. In other words, it’s not the solid mothball that works as a pest repellent, but these sublimating gases. This means if you’re near mothballs, you’re inhaling mothball gas. Wonderful!

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Mothballs

What Are Mothballs? Are They Bad For Your Health?

Kyler

You’ve probably smelled that weird, dank, but mostly musty odor that seems to follow some people around.

Generally unpleasant, it’s sometimes described as “old people smell”.

But the scent actually has less to do with the person themselves, and more to do with what they’ve used on their clothes – mothballs.

So, what exactly are mothballs? Why do they smell that way; should you use them; and, most importantly, are they safe?

Mothball Uses

Mothballs are used for what you probably think they’re used for – moths.

Okay, so they’re actually used against moths as a repellent.

But yeah, moths like to eat clothes, so our mothball companions were the solution designed to make them go away.

You’re supposed to place the them into an airtight bag or container along with your clothes. The keyword here is supposed.

Leaving things to air out, according to the mothball companies, may reduce the efficacy of your mothballs.

What’s in a Mothball?

Given their smell, most of us are probably curious to know just what kind of chemicals are inside of mothballs.

Mothballs are typically made with either naphthalene or 1,4-dichlorobenzene, both of which are toxic to humans and pets.

While these chemicals are solid at room temperature, and can be molded into mothballs, they will gradually change to gas over time, emitting fumes into the air (and that’s where the mothball odor comes from).

Both naphthalene and 1,4-dichlorobenzene can cause headaches, nausea, eye and nose irritation, and coughing.

Naphthalene is also a possible carcinogen, and can cause more serious issues like hemolytic anemia.

How Bad Are Mothballs, Really?

We already mentioned some of the respiratory problems that can come along from mothball fumes.

But even if you don’t plan on sniffing or eating mothballs, you should know how these products work.

The compounds inside of a mothball sublimate – meaning they go straight from solid to gas – by design.

So yes, the fumes that can make you ill are intentionally released; that’s how mothballs are supposed to work.

In other words, it’s not the solid mothball that works as a pest repellent, but these sublimating gases.

This means if you’re near mothballs, you’re inhaling mothball gas. Wonderful!

And this all brings us to urinal cakes.

Once upon a time, urinal cakes were made with naphthalene and 1,4-dichlorobenzene.

But they are not anymore, and do you know why? Because of the same health hazards we just mentioned!

So in short, don’t use mothballs, because we literally treat our pee better than that.

Maybe we should let the bugs in? Look at some here.

Kyler is a content writer at Sporcle. He currently spends most of his time hitting the university grind while drinking black coffee like water.

https://www.sporcle.com/blog/2020/02/what-are-mothballs-are-they-bad-for-your-health/

WATER DEFINITION IN CHEMISTRY - Water is a chemical compound consisting of two hydrogen atoms and one oxygen atom. The name water typically refers to the liquid state of the compound. The solid phase is known as ice and the gas phase is called steam. Under certain conditions, water also forms a supercritical fluid. Water is the main compound found in living organisms. Approximately 62 percent of the human body is water. In its liquid form, water is transparent and nearly colorless. Large volumes of liquid water and ice are blue. The reason for the blue color is the weak absorption of light at the red end of the visible spectrum. Pure water is flavorless and odorless. About 71 percent of the Earth's surface is covered by water. Only about 2.5 percent of the Earth's water is freshwater. Water is the third most abundant molecule in the universe, after hydrogen gas (H2) and carbon monoxide (CO). The chemical bonds between hydrogen and oxygen atoms in a water molecule are polar covalent bonds. Water readily forms hydrogen bonds with other water molecules.

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Water Definition in Chemistry

By Anne Marie Helmenstine, Ph.D.

Of all the molecules in the universe, the one most important to humanity is water.

Water Definition

Water is a chemical compound consisting of two hydrogen atoms and one oxygen atom.

The name water typically refers to the liquid state of the compound.

The solid phase is known as ice and the gas phase is called steam.

Under certain conditions, water also forms a supercritical fluid.

Other Names for Water

The IUPAC name for water is, actually, water. The alternative name is oxidane.

The name oxidane is only used in chemistry as the mononuclear parent hydride to name derivatives of water.

Other names for water include:

·         Dihydrogen monoxide or DHMO

·         Hydrogen hydroxide (HH or HOH)

·         H₂O

·         Hydrogen monoxide

·         Dihydrogen oxide

·         Hydric acid

·         Hydrohydroxic acid

·         Hydrol

·         Hydrogen oxide

·        The polarized form of water, H⁺ OH^-, is called hydron hyroxide.

The word "water" comes from the Old English word wæter or from the Proto-Germanic watar or German Wasser.

All of these words mean "water" or "wet."

Important Water Facts

·     Water is the main compound found in living organisms. Approximately 62 percent of the human body is water.

·     In its liquid form, water is transparent and nearly colorless. Large volumes of liquid water and ice are blue. The reason for the blue color is the weak absorption of light at the red end of the visible spectrum.

·     Pure water is flavorless and odorless.

·     About 71 percent of the Earth's surface is covered by water. Breaking it down, 96.5 percent of the water in the Earth's crust is found in oceans, 1.7 percent in ice caps and glaciers, 1.7 percent in groundwater, a small fraction in rivers and lakes, and 0.001 percent in clouds, water vapor, and precipitation.

·     Only about 2.5 percent of the Earth's water is freshwater. Nearly all of that water (98.8 percent) is in ice and groundwater.

·    Water is the third most abundant molecule in the universe, after hydrogen gas (H₂) and carbon monoxide (CO).

·    The chemical bonds between hydrogen and oxygen atoms in a water molecule are polar covalent bonds. Water readily forms hydrogen bonds with other water molecules.

   One water molecule may participate in a maximum of four hydrogen bonds with other species.

·    Water has an extraordinarily high specific heat capacity [4.1814 J/(g·K) at 25 degrees C] and also a high heat of vaporization [40.65 kJ/mol or 2257 kJ/kg at the normal boiling point]. Both of these properties are a result of hydrogen bonding between neighboring water molecules.

·    Water is nearly transparent to visible light and the regions of the ultraviolet and infrared spectrum near the visible range. The molecule absorbs infrared light, ultraviolet light, and microwave radiation.

·     Water is an excellent solvent because of its polarity and high dielectric constant. Polar and ionic substances dissolve well in water, including acids, alcohols, and many salts.

·      Water displays capillary action because of its strong adhesive and cohesive forces.

·      Hydrogen bonding between water molecules also gives it high surface tension. This is the reason why small animals and insects can walk on water.

·      Pure water is an electrical insulator. However, even deionized water contains ions because water undergoes auto-ionization.

   Most water contains trace amounts of solute. Often the solute is salt, which dissociates into ions and increases the conductivity of water.

·     The density of water is about one gram per cubic centimeter. Regular ice is less dense than water and floats on it. Very few other substances exhibit this behavior.

   Paraffin and silica are other examples of substances that form lighter solids than liquids.

·      The molar mass of water is 18.01528 g/mol.

·      The melting point of water is 0.00 degrees C (32.00 degrees F; 273.15 K). Note the melting and freezing points of water may be different from each other. Water readily undergoes supercooling. It can remain in liquid state well below its melting point.

·      The boiling point of water is 99.98 degrees C (211.96 degrees F; 373.13 K).

·      Water is amphoteric. In other words, it can act as both an acid and as a base.

Anne Marie Helmenstine, Ph.D.

Chemistry Expert

Education

Ph.D., Biomedical Sciences, University of Tennessee at Knoxville

B.A., Physics and Mathematics, Hastings College

Introduction

Ph.D. in biomedical sciences from the University of Tennessee at Knoxville - Oak Ridge National Laboratory.

Science educator with experience teaching chemistry, biology, astronomy, and physics at the high school, college, and graduate levels.

ThoughtCo and About Education chemistry expert since 2001.

Widely-published graphic artist, responsible for printable periodic tables and other illustrations used in science.

Experience

Anne Helmenstine, Ph.D. has covered chemistry for ThoughtCo and About Education since 2001, and other sciences since 2013. She taught chemistry, biology, astronomy, and physics at the high school, college, and graduate levels. She has worked as a research scientist and also abstracting and indexing diverse scientific literature for the Department of Energy.

In addition to her work as a science writer, Dr. Helmenstine currently serves as a scientific consultant, specializing in problems requiring an interdisciplinary approach. Previously, she worked as a research scientist and college professor. 

Education

Dr. Helmenstine holds a Ph.D. in biomedical sciences from the University of Tennessee at Knoxville and a B.A. in physics and mathematics with a minor in chemistry from Hastings College. In her doctoral work, Dr. Helmenstine developed ultra-sensitive chemical detection and medical diagnostic tests.

ThoughtCo and Dotdash

ThoughtCo is a premier reference site focusing on expert-created education content. We are one of the top-10 information sites in the world as rated by comScore, a leading Internet measurement company. Every month, more than 13 million readers seek answers to their questions on ThoughtCo.

For more than 20 years, Dotdash brands have been helping people find answers, solve problems, and get inspired. We are one of the top-20 largest content publishers on the Internet according to comScore, and reach more than 30% of the U.S. population monthly. Our brands collectively have won more than 20 industry awards in the last year alone, and recently Dotdash was named Publisher of the Year by Digiday, a leading industry publication.

https://www.thoughtco.com/definition-of-water-in-chemistry-605946

DRINKING WATER FROM A HOSE - Garden hoses, unlike plumbing inside your home, aren't manufactured to deliver safe drinking water. Lead, BPA, and phthalates are used in garden hoses mainly to stabilize the plastics. The most common plastic is polyvinyl chloride, which may release toxic vinyl chloride. Antimony and bromine are components of flame retardant chemicals. Half the hoses contained antimony, which is linked to liver, kidney, and other organ damage. All of the randomly selected hoses contained extremely high levels of phthalates, which can lower intelligence, damage the endocrine system, and cause behavioral changes. The water from a hose isn't safe for you to drink, it's not good for your pets, and it might transfer nasty chemicals to garden produce. So, what can you do to reduce the risk? Let the water run. The worst of the contamination comes from water that has been sitting in the hose a while. If you let the water run for a few minutes, you'll greatly reduce the number of toxins.

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Drinking Water From a Hose

Is It Safe to Drink Water From a Hose?

How Dangerous Is Hose Water?

By Anne Marie Helmenstine, Ph.D.

It's a hot summer day and the cool water from the garden hose or sprinkler seems so inviting. Yet, you've been warned not to drink it. How dangerous could it be?

The truth is, the warning is based on fact. Do not drink water from the hose. 

Garden hoses, unlike plumbing inside your home, aren't manufactured to deliver safe drinking water.

In addition to bacteria, mold, and possibly the odd frog, the water from a garden hose typically contains the following toxic chemicals:

·         lead

·         antimony

·         bromine

·         organotin

·         phthalates

·         BPA (bisphenol A)

Lead, BPA, and phthalates are used in garden hoses mainly to stabilize the plastics.

The most common plastic is polyvinyl chloride, which may release toxic vinyl chloride.

Antimony and bromine are components of flame retardant chemicals.

A study conducted by the Ecology Center in Ann Arbor, M.I. (healthystuff.org), found lead levels exceeded the safety limits set by the Safe Water Drinking Act in 100% of the garden hoses they tested.

A third of the hoses contained organotin, which disrupts the endocrine system.

Half the hoses contained antimony, which is linked to liver, kidney, and other organ damage.

All of the randomly selected hoses contained extremely high levels of phthalates, which can lower intelligence, damage the endocrine system, and cause behavioral changes.

How to Reduce the Risk

The water from a hose isn't safe for you to drink, it's not good for your pets, and it might transfer nasty chemicals to garden produce. So, what can you do to reduce the risk?

·      Let the water run. The worst of the contamination comes from water that has been sitting in the hose a while. If you let the water run for a few minutes, you'll greatly reduce the number of toxins.

·      Store the hose in a dark, cool place. Sunlight and warmer temperatures increase the rate of degradation of the polymers and leaching of undesirable chemicals into the water.

·      You can slow down these processes by protecting the hose from excess light and heat.

·      Switch to a safer hose. Natural rubbers hoses are available that are manufactured without toxic plasticizers.

Read the label when selecting a new garden hose and choose one that says it has a low environmental impact or is safe for drinking water (potable water).

While these hoses are safe to use, it's still a good idea to let the water run a few minutes to remove undesirable chemicals or pathogens on the surface of the hose.

·      Be mindful of the fixture. Most outdoor plumbing fixtures are brass, which is not regulated to deliver potable water and usually contain lead.

No matter how safe your hose may be, be aware the water may still contain heavy metal contamination from the faucet.

Most of this contamination is removed once the water has run through the fixture, but this is the water furthest from the end of the hose.

It's worth repeating: If you must drink from the hose, let the water run before taking a sip.

Anne Marie Helmenstine, Ph.D.

Chemistry Expert

Education

Ph.D., Biomedical Sciences, University of Tennessee at Knoxville

B.A., Physics and Mathematics, Hastings College

Introduction

Ph.D. in biomedical sciences from the University of Tennessee at Knoxville - Oak Ridge National Laboratory.

Science educator with experience teaching chemistry, biology, astronomy, and physics at the high school, college, and graduate levels.

ThoughtCo and About Education chemistry expert since 2001.

Widely-published graphic artist, responsible for printable periodic tables and other illustrations used in science.

Experience

Anne Helmenstine, Ph.D. has covered chemistry for ThoughtCo and About Education since 2001, and other sciences since 2013. She taught chemistry, biology, astronomy, and physics at the high school, college, and graduate levels. She has worked as a research scientist and also abstracting and indexing diverse scientific literature for the Department of Energy.

In addition to her work as a science writer, Dr. Helmenstine currently serves as a scientific consultant, specializing in problems requiring an interdisciplinary approach. Previously, she worked as a research scientist and college professor.

Education

Dr. Helmenstine holds a Ph.D. in biomedical sciences from the University of Tennessee at Knoxville and a B.A. in physics and mathematics with a minor in chemistry from Hastings College. In her doctoral work, Dr. Helmenstine developed ultra-sensitive chemical detection and medical diagnostic tests.

ThoughtCo and Dotdash

ThoughtCo is a premier reference site focusing on expert-created education content. We are one of the top-10 information sites in the world as rated by comScore, a leading Internet measurement company. Every month, more than 13 million readers seek answers to their questions on ThoughtCo.

For more than 20 years, Dotdash brands have been helping people find answers, solve problems, and get inspired. We are one of the top-20 largest content publishers on the Internet according to comScore, and reach more than 30% of the U.S. population monthly. Our brands collectively have won more than 20 industry awards in the last year alone, and recently Dotdash was named Publisher of the Year by Digiday, a leading industry publication.

https://www.thoughtco.com/is-it-safe-to-drink-hose-water-609429

HOT AND HIGH AIRPORTS - Some Airports Have Unusually Long Runways - Operating at an airport that has been identified as one of these ‘hot and high’ airports or has such atmospheric conditions at the time of taking off or landing, can be a difficult task for pilots. It has to do with air density, which decreases with an increase in temperature and altitude. At an airport with such conditions, taking off becomes difficult, as lower air density translates to less lift being generated by the wings or the rotors of the airplane. Lower air density also hampers the performance of aircraft engines, potentially jeopardizing the flight’s safety. Light aircraft and older helicopters often end up stalling in ‘hot and high’ conditions in a bid to maintain level flight, as their service ceilings are pretty low. There are some other grave risks involved too; sometimes, the airplane cannot climb rapidly enough to clear the surrounding terrain; things gets worse if the airport is in a mountainous region or is surrounded by mountains, buildings and other tall structures.

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Hot And High Airports

Why Do Some Airports Have Unusually Long Runways?

Ashish 

After our airplane touched down on the runway the other day, I had a rather unusual feeling; I felt as if the airplane was running for too long on the runway.

At first, I discarded the thought, but later on, I came to know that the runway was unusually longer than regular runways!

Upon further investigation, I realized that the particular airport I took off from was ‘hot and high’.

After brushing aside the literal meaning of the phrase, I stumbled upon what is probably one of the smartest tweaks that humans have made to the aviation industry.

What is ‘hot and high’ in the aviation industry?

 ‘Hot and high’ is a phrase often used in the aviation industry, and it’s used to refer to the condition of high ambient temperature, as well as high elevation of the airport.

Such conditions impact the flight of airplanes, and hence become a serious cause of concern, as they significantly influence the safety of the airplanes flying in such regions.

Let’s break down the term ‘hot and high’.

‘Hot’ is pretty intuitive; it is representative of a high ambient temperature of the region.

Since temperature is a variable physical quantity (i.e., its value changes continuously), the severity of the ‘hot and high’ condition also changes.

On other hand, ‘high’ refers to the elevation of the airport in question.

If it’s built on land that has more elevation than the standard terrestrial height, it’s said to be a ‘high’ airport.

There are several prominent ‘hot and high’ airports, including Albuquerque (New Mexico), Brasília (Brazil), Canberra (Australia), Denver (Colorado) and Siachen Glacier (India).

The fact that ambient temperature tends to be lower at high altitudes mitigates the ‘hot and high’ effect to some extent.

What’s the challenge with a ‘hot and high’ airport?

Operating at an airport that has been identified as one of these ‘hot and high’ airports or has such atmospheric conditions at the time of taking off or landing, can a difficult task for the airline pilots.

Why is that?

It has everything to do with air density, which is known to decrease with an increase in ambient temperature and altitude.

Therefore, at an airport with such conditions, taking off becomes particularly difficult, as lower air density translates to less lift being generated by the wings or the rotors of the airplane.

Not only that, lower air density also hampers the performance of aircraft engines, potentially jeopardizing the flight’s safety.

Light aircraft and older helicopters often end up stalling in ‘hot and high’ conditions in a bid to maintain level flight, as their service ceilings (maximum usable altitude of an aircraft) are pretty low.

There are some other grave risks involved too; sometimes, the airplane cannot climb rapidly enough to clear the surrounding terrain; things gets worse if the airport is in a mountainous region or is surrounded by mountains, buildings and other tall structures.

How do they tackle this problem?

Since both the atmospheric conditions involved here, namely the hotness and elevation of a region, are artificially unalterable, you need artificially controllable alternatives that can help overcome this challenge.

The most commonly used technique at airports with such natural conditions is making particularly long (longer than usual) runways.

This increases aircraft take-off run distance, hence providing more energy for the subsequent climb into the sky.

Reducing the total weight of the aircraft can also help; this is often achieved by using up excess fuel or removing not-so-vital equipment from the aircraft.

Airplanes often circle over the destination a few times to consume excess oil so that they are left with only enough oil to make a successful landing.

Structural changes in aircraft, such as more powerful engines and bigger wings, can also help guarantee a smooth take-off or landing.

Other techniques, such as additional high-lift devices, the injection of distilled water, and assisted take-offs can also compensate for ‘hot and high’ conditions.

So, next time your airplane is running on a runway that just never seems to end, you’ll know that the airport likely has weather conditions that are a bit out of the ordinary.

In other words, it’s a good thing someone was thinking ahead!

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spends a lot of time watching movies, and an awful lot more time discussing them. He likes Harry Potter and the Avengers, and obsesses over how thoroughly Science dictates every aspect of life… in this universe, at least.

https://www.scienceabc.com/pure-sciences/airports-unusually-long-runways.html