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Trench Attack

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Imagine that you are a military commander. You have been fighting an enemy platoon for weeks on end, and neither side has made any progress. Both you and the enemy have dug trenches to protect yourselves and hold your position. The only way that you can win the battle is to use chemical agents against the enemy. Your task is to research the chemicals you have at your disposal and the methods you have of dispersing them so that you can affect as many of the enemy soldiers as possible. You don’t have much time before your troops run out of supplies, so dig in, get your gas mask on, and get going!

Planning and Carrying Out Investigations

Trench Attack Brochure

Trench Attack Brochure

What is a chemical agent?

A chemical agent is any toxic chemical compound used to harm other people. These chemical agents can be used as weapons in chemical warfare. Chemical agents have negative effects to the health of humans. Since there are so many different chemical agents, there are a large range of symptoms that these agents can cause. Some mild chemical agents, like tear gas and pepper spray, are used by police for crowd control, but these agents do not cause permanent harm. Other chemical agents have much worse effects, and can even be deadly. For example, mustard gas can cause painful blisters on the skin, blindness, or even death.

When were chemical agents first used?

Chemical agents were first used during World War 1. Tear gas used in August 1914, making it the first chemical weapon used, but it was largely ineffective and didn't cause fatalities or even injuries. The Germans, looking for a stronger agent, developed chlorine gas, which can cause damage to the eyes, nose, throat, and lungs. Chlorine gas was introduced in 1915, and was effectively used in the Second Battle of Ypres. Because chlorine gas is a yellow-green gas and has a strong odor, it was easily detected and soldiers could therefore identify the threat and move away quickly. Also introduced in 1915 was a far more deadly gas, phosgene. Phosgene was colorless and smelled like moldy hay, making it much more difficult to detect than chlorine gas. 85% of the 100,000 deaths that occurred in World War 1 due to chemical weapons were due to phosgene. Another effective poison gas that was utilized was mustard gas. Mustard gas causes blisters on the skin, blindness, vomiting, internal and external bleeding, trouble breathing, and can potentially cause death. As time went on, the number of deaths from poison gas decreased as soldiers began using gas masks, covering their nose and mouths with cloth, and wearing goggles to protect their eyes.

How does mustard gas work?

Mustard gas has a yellowish brown color and has a mustard, garlic, or horseradish odor. It easily penetrates clothes and any contact with the skin will cause itching and skin irritation within 24 hours after the exposure. The skin irritation will eventually turn into a chemical burn, which becomes large blisters with yellow fluid inside. If the victim's eyes were exposed to the mustard gas, they would become sore due to conjunctivitis (also known as pink eye). Later, the eyelids will swell, leading to temporary blindness. If victims are exposed to very high levels of mustard gas, the chemical agent can cause bleeding and blistering of the respiratory system as the victim breathes in the gas. The chemical burns on the skin can vary between first and second degree burns. Very serious burns can be as severe and disfiguring as third degree burns. If more than 50% of the victim's skin has been burned, the burn is often fatal.

How does chlorine gas work?

When chlorine gas is breathed in, the victim will start to cough, vomit, and their eyes will be irritated. If high levels of chlorine gas are inhaled, victims will experience a burning sensation in their throat and chest pains. This is because the chlorine molecule reacts with water in the lungs to form hydrochloric acid, which can be lethal. If enough chlorine gas is inhaled, it destroys the respiratory organs of its victims, who die a slow death by asphyxiation.

How does weather affect gas dispersion?

Weather affects gas dispersion in numerous ways. Temperature affects the manner in which gas disperses. Heat makes gases expand and increase in volume. In hotter temperatures, gases will disperse over a greater area than cooler temperatures. Density also has an effect on the location of the gas dispersion. If the gas is warmed and is less dense than the air, it will rise, but if it is cooled and denser than the air, it will sink. Wind also plays a role in gas dispersion. The gas will be swept away with the wind and its location will be determined by the strength and direction of the wind. If there is precipitation in the form of rain or snow, the gas will be washed away or absorbed by it.
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