Answer:
Helium. Symbol for Helium is: He . The atomic number (Z) is: 2. The mass number (A): 4. Common human uses of the element: Because it is very unreactive, helium is used to provide an inert protective atmosphere for making fiber optics and semiconductors, and for arc welding. Helium is also used to detect leaks, such as in car air-conditioning systems, and because it diffuses quickly it is used to inflate car airbags after impact. present in a common molecule: Helium does not bond with the other atoms. if its dangerous: helium can cut off oxygen supply or can cause an embolism if a person inhales too deeply.
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Carbon. Symbol: C. The atomic number (Z): 6. The mass number (A): 12. Common human uses of the carbon: is used in metal smelting. It is particularly important in the iron and steel industries. Graphite is used in pencils, to make brushes in electric motors and in furnace linings. Activated charcoal is used for purification and filtration. The carbon atom has unique properties that allow it to form covalent bonds to as many as four different atoms, making this versatile element ideal to serve as the basic structural component, or “backbone,” of the macromolecules. Individual carbon atoms have an incomplete outermost electron shell. If its dangerous: Elemental carbon is of very low toxicity. Health hazard data presented here is based on exposures to carbon black, not elemental carbon. Chronic inhalation exposure to carbon black may result in temporary or permanent damage to lungs and heart.
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Sodium. The Symbol: Na. Atomic number: 11. Mass number: 23. Common human uses : Sodium is important for many different functions of the human body. For example, it helps cells to transmit nerve signals and regulate water levels in tissues and blood. Sodium is the sixth most common element on Earth, and makes up 2.6% of the Earth's crust. The most common compound is sodium chloride. The most common compound of sodium is sodium chloride (common salt). If its dangerous: Sodium is essential to human health, but too much sodium is poisonous. Sodium poisoning can cause seizures, coma, and death.
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Nitrogen. Symbol: N. Atomic number :7. Mass number: 14. Common human uses :Human activities, such as making fertilizers and burning fossil fuels, have significantly altered the amount of fixed nitrogen in the Earth's ecosystems. If its present in a common molecule: Common compounds with nitrogen atoms include ammonia (NH3), nitrous oxide (N2O), nitrites, and nitrates. Nitrogen is also found in organic compounds such as amines, amides, and nitro groups. If its dangerous: High concentrations of nitrogen gas can be particularly harmful to human health. Nitrogen can displace oxygen from ambient air within an enclosed space leading to a dangerous build-up of the inert gas.
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Potassium. Symbol: K. Atomic number: 19. Mass number:39. Common human uses: Potassium is a mineral that plays many important roles in the body. Food sources of potassium include fruits (especially dried fruits), cereals, beans, milk, and vegetables. Potassium is most commonly used for treating and preventing low potassium levels, treating high blood pressure, and preventing stroke. If its present in a common molecule: Potassium forms many important compounds. Potassium chloride (KCl) is the most common potassium compound. It is used in fertilizers, as a salt substitute and to produce other chemicals. Potassium hydroxide (KOH) is used to make soaps, detergents and drain cleaners. If its dangerous: Having too much potassium in your blood can be dangerous. Potassium affects the way your heart's muscles work. When you have too much potassium, your heart may beat irregularly, which in the worst cases, can cause heart attack.
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