What leathal substances come out of a volcano when they erupt?

Question

i need this for a school project!!

Answer 1

hydrogen sulfide (H2S), hydrogen (H2), carbon monoxide (CO), hydrogen chloride (HCL), hydrogen fluoride (HF), and helium (He).

read this website it will help you.

http://volcanoes.usgs.gov/Hazards/What/V...

Answer 2

All of the above plus CO2. The most common volcanic gases are water vapor (90%), carbon dioxide, sulfur dioxide, hydrogen sulfide, and hydrogen. Sulfur dioxide gas can react downwind with water droplets in the atmosphere and fall as acid rain, causing corrosion, and adversely affecting vegetation. Carbon dioxide is heavier than air and tends to collect in depressions, where on occasion, it can accumulate in lethal concentrations and cause people and animals to suffocate.

Pyroclastic flows and surges are high-speed avalanches of hot ash, rock fragments, and gas that move down the sides of a volcano during explosive eruptions or when the steep edge of a dome breaks apart and collapses. These pyroclastic flows, which can reach 1,500 degrees Fahrenheit and move at 100-150 miles per hour, are capable of knocking down and burning everything in their paths. A more energetic and dilute mixture of searing gas and rock fragments is called a pyroclastic surge. Surges move easily up and over ridges, while flows tend to follow valleys. For example, more than 2,000 people died from pyroclastic surges during the 1982 eruption of El Chichon in southern Mexico.

Molten rock, or magma, that pours onto the Earth's surface is called lava. The higher a lava's silica content, the more viscous it becomes. Low-silica basalt lava can form fast-moving (10-30 miles per hour), narrow lava streams or spread out into broad sheets up to several miles wide. Between 1983 and 1993, basalt lava flows erupted at Kilauea Volcano in Hawaii destroying nearly 200 houses and severing the coast highway along the volcano's south flank.

Major hazards of lava flows include, burying, crushing, covering, and burning everything in their path. Sometimes lava melts ice and snow to cause floods and lahars.

When a volcano erupts it will sometimes eject material known as tephra, i.e. rock fragments, into the atmosphere. The largest pieces of tephra are called blocks and bombs. Blocks and bombs are normally shot ballistically from the volcano, and because they are so large, they tend to fall near their source. Blocks and bombs as large as 8-30 tons have fallen as far as .6 miles or 1 kilometer from their source. Small blocks and bombs have been known to travel as far away as 12-50 miles. Smaller ejecta, such as lapilli 0.5-16 inches in size and ash less than 0.5 inches, which are lifted upward by the heat of the eruption, will fall farther from the volcano.

Tephra produces a wide range of hazards. When the ejected material is in the atmosphere, it is electrically charged and often produces lightning, which has killed a number of people. Large ejecta shot ballistically from the volcano are also a hazard to those unfortunate enough to be near the volcano. Other hazards are produced when the ash is deposited on the ground. Ash can disrupt electricity, television, radio, and telephone communication lines, bury roads and other manmade structures, damage machinery, start fires, and clog drainage and sewage systems.

Ash can also produce poor visibility and cause respiratory problems. Often people living in areas affected by volcanic ash will wear filter masks or wet cloths over their nose and mouth to protect themselves from breathing in volcanic ash and fumes. If ash builds up on the tops of roofs, it will often cause structural collapse. This is especially common of flat-topped buildings. Most of the deaths resulting from the eruption of Mount Pinatubo in 1991 were due to collapsing roofs.

Answer 3

smelly crud.