1. Radium
   Helium
2. Selenium
   Nickel

What else could make balloons and blimps float in the air but a full dose of helium? This gas is also found in scuba tanks, where it's mixed with oxygen for a better diving experience. And no matter how funny it makes your voice sound, it's never safe to inhale helium gas for fun. It can be deadly.

1. Aluminum
   Oxygen
2. Boron
   Sulfur

Aluminum is a lightweight metal found in airplanes, soda cans and pots and pans. In addition to its light weight, this material is used in a wide variety of applications because it is both non-corrosive and highly malleable.

1. Neon
   Hydrogen
2. Copper
   Carbon

Carbon is found in every single organic compound in the world. That includes you, your pets and the plants all around you. It's also found in coal, oil, gas, graphite and diamonds.

1. Mercury
   Tin
2. Gold
   Sodium

Gold has been one of the most valuable and highly desirable metals in the world for thousands of years. It's not only beautiful and malleable, but also prized for its golden color and the fact that it doesn't tarnish like silver.

1. Tungsten
   Iron
2. Titanium
   Radium

Iron is a hard, magnetic metal used to make cars, buildings and heavy machinery. It's often mixed with others metals to form alloys, such as steel, chromium or stainless steel, which helps to improve its strength and reduce the risk of corrosion.

1. Nitrogen
   Helium
2. Manganese
   Phosphorus

Nitrogen makes up around 80 percent of the Earth's atmosphere. It's also used to make nylon, explosives and fertilizers.

1. Nickel
   Oxygen
2. Cadmium
   Tin

You may have heard of oxygen. It's that stuff in the air that you breathe in to keep you alive. This gas happens to be the third most abundant element known to man, and is used in welding as well as in the production of rocket fuel.

1. Lithium
   Boron
2. Sodium
   Aluminum

Sodium combines with chlorine to form a compound known as NaCl -- you might know it as table salt. It's also used to give a yellow hue to certain types of street lights, and found in sodium bicarbonate -- also known as baking soda.

1. Mercury
   Chlorine
2. Iron
   Sulfur

Most sulfur is used to make sulfuric acid, which is used to make batteries, fertilizer and gunpowder. That rotten egg smell you associate with sulfur is only associated with hydrogen sulfide -- pure sulfur is actually odorless.

1. Potassium
   Gold
2. Silver
   Lead

Potassium is a soft, highly reactive metallic element. It's found in soaps, cleaners and fertilizers, but is almost always used in the form of a compound. Combined with chloride, it makes a common fertilizer, while potassium hydroxide is found in many cleaning supplies.

1. Neon
   Radium
2. Boron
   Chloride

Chloride actually shows up quite a bit in several everyday objects. It makes up one half of NaCl, or common table salt. It's also used to make bleach and pool chemicals.

1. Copper
   Lithium
2. Oxygen
   Fluorine

Copper is a metallic element known for being resistant to corrosion and an excellent conductor. It's used to make pennies, electrical wiring, motors and heating and cooling components. Because of its attractive hue, it's also used in decorative items, roofing and cookware.

1. Rhodium
   neon
2. Hydrogen
   Calcium

Hydrogen is the most abundant of all known elements. Built from a single proton combined with a single electron, it's used to make ammonia and various fuels, including rocket fuel.

1. Neon
   Cadmium
2. Copper
   Mercury

Mercury -- once referred to as quick silver because it forms a shiny liquid pool at room temperature -- is both beautiful and toxic. Named for the planet Mercury, it's used in thermometers, old dental fillings and to make a red pigment called vermilion.

1. boron
   Lithium
2. Iron
   Potassium

Lithium is the lightest of all the known metals. It's used in batteries and metal alloys, and also serves as a surprisingly effective medicine for treating patients with bipolar disease and mood disorders.

1. Boron
   Calcium
2. Iron
   Tungsten

Boron is used in borax -- a household chemical used to clean laundry, and in some homemade slime-making recipes. This element is used to add a green tinge to pyrotechnics, and is also found in ceramic glaze and certain types of eye drops.

1. Gold
   Tin
2. Sodium
   Chlorine

Tin is rarely used to make cans anymore, except as a coating over steel, but this soft metal is found in plenty of common products. It's used in solder for joining metal, and when mixed with copper, it forms pewter.

1. Helium
   Nitrogen
2. Chromium
   Oxygen

You know that shiny chrome plating on cars and motorcycles? Thank chromium for that. This compound is also used to make stainless steel and other alloys.

1. Gold
   Silver
2. Radium
   Nickel

Nickel is a relatively hard metal that happens to be magnetic, like iron. It's primarily added to other metal products to improve corrosion-resistance. Many pipes, tubes and desalination equipment are combined with or coated with nickel.

1. Nitrogen
   Tungsten
2. Oxygen
   Lead

Tungsten has the highest melting point of any metal. That makes it a solid choice for steel, light bulb filaments and other applications where heat exposure could pose a challenge for other materials.

1. Fluorine
   Cadmium
2. Lead
   Iron

In its natural state, fluorine is a poisonous gas, but when combined with other elements, it's found in many everyday items. Not only is it added to toothpaste and drinking water, but it's also used in manufacturing to dissolve or etch materials.

1. Iodine
   Barium
2. Neon
   Nitrogen

The glow of a neon sign has long been a bright beacon on a dark night, helping us find bars and businesses in low light. This natural element is not only used in advertising signs, like that "Open" on your local convenience store, but also in lasers and certain types of indicator lights.

1. Zirconium
   Lead
2. Cobalt
   Magnesium

Magnesium is one of the lightest metals on the periodic table. It's used to make Epsom salts, medicine and Magnesium Hydroxide.

1. Arsenic
   Silver
2. Silicon
   Lead

Silicon is such a useful element that the heart of the entire tech industry is named after it in the form of Silicon Valley. This hard metal element is used to make semiconductors, computers and other electronics.

1. Selenium
   Phosphorus
2. Rhodium
   Sodium

In its purest state, phosphorous is a solid white wax that glows. It's used to make explosives, fertilizes and pyrotechnics.

1. Oxygen
   Iron
2. Argon
   Hydrogen

Argon is a non-metallic gas at room temperature. It serves as the filling inside many traditional light bulbs, and is also used in both welding and semiconductor manufacturing.

1. Titanium
   Cadmium
2. Tin
   Lead

Titanium has impressive strength compared to its weight, and can also tolerate extreme temperatures better than many other metals. Because of this, it's popular for building engines and space shuttles that may be subject to intense heat.

1. Arsenic
   Manganese
2. Lead
   Iodine

A substantial portion of the Earth's crust is made from a hard metal element called manganese. It's also used to make batteries, as well as to counteract the effects of iron in glassmaking. Without the addition of manganese, iron would give glass a greenish tinge.

1. Silver
   Mercury
2. Cobalt
   Silicon

Cobalt is a hard, magnetic metal. One of its isotopes is a critical form of therapy for treating cancer. This solid is also used in electroplating, jet engines, and as a coloring agent for making glass and pottery.

1. Silver
   Tin
2. Lead
   Gold

Move over copper -- silver is actually one of the best conductors of all the metallic elements. This soft, shiny metal is also a great reflector of light, making it a popular choice for jewelry and high-end tableware.

1. Selenium
   Cobalt
2. Oxygen
   Zinc

Got brass door knobs or candlesticks? Then you've got yourself some zinc. When combined with copper, zinc forms the golden metal known as brass. This element is also used to make paint, rubber, cosmetics and batteries.

1. Bismuth
   Nitrogen
2. Arsenic
   Hydrogen

At one point in history, arsenic was such a popular poison that it was known as "the inheritance powder." Today, this fragile metal is used to make insecticides and transistors.

1. Mercury
   Selenium
2. Boron
   Hydrogen

Selenium is an element that is gray and brittle in its solid, natural state. Combined with other elements, selenium plays an important role in the manufacture of solar panels and photovoltaic cells.

1. Zirconium
   Helium
2. Oxygen
   Nitrogen

Zirconium is a rare element in that it is not only non-corrosive, but also neutron-resistant. This means it is used in mechanical elements, like pumps and valves, but also in nuclear reactors because it does not absorb the neutrons.

1. Zinc
   Rhodium
2. Nitrogen
   Hydrogen

Rhodium is a metal that is corrosion-resistant and surprisingly shiny. It's used to make spark plugs, catalytic converters and other electrical elements.

1. Fluorine
   Neon
2. Cadmium
   Silicon

Cadmium is a toxic, posionous metal -- similar to lead. It is used in nickel-cadmium batteries, and is also a crucial part of nuclear technology.

1. Iodine
   Calcium
2. Sodium
   Chlorine

In its natural state, iodine is a purplish-black solid. It has long been used in medicine, particularly as an antiseptic. A radioactive isotope of this element is also used to treat thyroid conditions.

1. Cobalt
   Silver
2. Gold
   Barium

Barium is a soft metal with one very important claim to fame: Its ability to absorb X-rays. It's also used to lend a green flow during pyrotechnics displays, and can be used to remove gases from vacuum tubes in the lab.

1. Lead
   Sodium
2. Neon
   Oxygen

Lead is a soft, non-corrosive metal that is also highly toxic -- and no, it's no longer used in pencils -- that's graphite. This element is used to create weights, batteries and for coating various types of wires.

1. Sodium
   Radium
2. Borin
   Bismuth

Bismuth is a very brittle metallic element. It has an unusually low melting point, which makes it a popular choice for fuses, fire detection systems and fire extinguishers.