Which floatation gas has been replaced by safer helium in airships?

The reason why helium is used instead of hydrogen in airships is that it's also light in weight, and the reason why hydrogen is replaced is because of its reaction with oxygen.

Hydrogen is explosive, helium not.

Yes. Helium isn't flammable, which makes it the safer option.

Helium is inert. Will not burn like hydrogen does so well.

Hydrogen is much more likely to ignite and cause a massive fire than helium (see Hindenburg disaster). Because Helium is much more stable than Hydrogen is is used in airships because it is a lot safer.

because hydrogen is flammable. in fact, forget that, its down right explosive.

Because Helium is inflammable and the safer choice.

helium is 2 times heavier than hydrogen helium is not so reactive , hydrogen is extremely flamable unlike helium.

Modern airships use Helium for lift which is non-combustible whereas in the past airships such as the Hindenburg used Hydrogen for lift which is highly combustible. In addition, modern airships take advantage of new alloys and polymers which give them a much stronger airframe.

Because helium is an non flammable gas, which proved a much safer alternative to the hydrogen airship following the explosion of the LZ129 Hindenburg on May 6th 1937.

In their early history, buoyant airships (zepellins, blimps) were filled with hydrogen, a highly flammable gas. Since the Hindenburg disaster, hydrogen has been supplanted by helium, a much more expensive material, but one that is inert and hence much safer.

because hydrogen used to be in those airships and since hydrogen is flammable it was very dangerous

Generally speaking, helium is safer, as it is an inert gas, but Hydrogen is cheaper to make and is lighter.

helium is a safer choice than hydrogen because helium is very reactive with oxygen while hydrogen is not

Hydrogen is extremely flammable and helium is safer.

Helium, but there are more limited supplies of it. At the time of the Hindenburg, the US was the sole source with all of it coming from Texas oil fields mixed in with the natural gas. It was there because of the combination of deep Uranium Ore deposits and Salt Domes, Uranium decay alphas captured electrons becoming Helium then got caught in the salt domes with the natural gas on top of the oil. The…

Yes Helium is safer than Oxygen, in that it does not feed combustion the way Oxygen does. In fact, a high concentration of Helium will extinguish a fire. BUT … In a closed area, you can suffocate if the concentration of Helium in the air gets too high.

Hydrogen is extremely flammable, helium is not flammable at all.

Helium is not reactive, cannot explode.

Yes, because helium doesn't react, burn or explode.

Helium is lighter than air. so helium balloons will rise up in air. also helium is chemically inert and safer to use.

Helium is inert whereas hydrogen is flammable and under some conditions explosive

Helium is less dense than nitrogen and oxygen, the main components or air. Any given volume of helium has less mass than the same volume of air at the same pressure. Balloons filled with helium therefor rise through air just as air bubbles rise up through denser, heavier water. A helium filled ballon expands as it rises displacing an increasing volume of air as it goes. This is because the air around it becomes thinner…

Hydrogen combines with oxygen with explosive force in the presence of a spark. Helium is an inert gas that will not burn or explode, so is much safer to use in balloons and air ships instead of hydrogen. The Hindenburg incident is a good example of why not to use hydrogen in a balloon. In the related links box below I posted an article on it. Helium is more chemically stable than hydrogen and will…

Because helium is an inert gas and won't burn (unlike hydrogen). See: Hindenburg.

Helium is much safer, so it is often used in balloons and blimps, not spacecraft. Hydrogen is still used as a fuel. Helium will not burn.

because hydrogen is flammable so you have to be very cautious.

Heavier but safer. Look what happened to the Hindenburg:(

helium is less dense than air so a balloon filled with helium will float. and it is inert - so safer to use than the very reactive hydrogen.

Hydrogen is highly flammable, while helium is inert - it doesn't burn or react much.

Yes, party balloons that float are filled with helium. Helium is used because it is lighter than air, causing the balloon to float upwards, but safer than the alternative hydrogen, which is explosive.

Helium is a noble gas ('inert' gas) - a gas that will not react with other elements to form compounds. There are several elements like this - Helium, neon, argon, krypton, xenon and radon. The latter three do form some compounds but only with great difficulty. In the periodic table of elements helium and all the other noble gases are classed as group 0 (or sometimes group 8). Their atoms all have complete shells (energy…

Although Hydrogen is one on the element scale, Helium is a preferred gas to use in balloons because it is a safer (not flammable) gas than hydrogen.

Not as flammable but more expensive and less lift-search "Hindenburg"

Helium will not burn. Hydrogen burns in air to form H2O (water) Thus in circumstances where a lite gas is required (e.g. in a balloon) it is safer to use Helium. see http://www.unmuseum.org/hindenburg.htm

During the time of the zeppelines, the US had more or less monopoly on Helium, and imposed an embargo on Germany on many things, one being Helium. The Hindenburg was designed for Helium, but had to turn to Hydrogen.

Hydrogen used to be used but was generally discontinued after the Hindenburg disaster (except for unmanned aircraft). Helium is not nearly as flammable as hydrogen and so is a safer gas to use.

Both hydrogen and helium are gaseous elements that are not as dense as the nitrogen and oxygen in air, and can be used to fill balloons to make them lighter-than-air. Helium is the least reactive of the two, and therefore safer to use.

Hot air balloons use hot air. They have a burner to heat the air. Hydrogen balloons were too dangerous because hydrogen is highly flammable, even static electricity could cause an explosion. Helium is safer because helium is not flammable.

The liquid is mercury; it has now been replaced with a cheaper and safer chemical.

All of the Apollo spacecraft landed in the ocean, which is where they were designed to land. 3/26/10--The USSR landed their spacecraft on dry land because they had endless expanses of dry land to use. NASA chose the ocean because it was considered a safer landing surface and even if they missed the target by hundreds of miles, the thing still landed in water. The Apollo capsules were designed to float for a period of…

the use of the oven replaced the spit and grill, this allowed for mre control of flame (heat) and sanitation

I would say that Thumb/Flash USB drives were what replaced the Floppy Drive, they have an advantage over the Floppy for being able to transport more data in a safer way.

Water won't affect the micro-chip embedded in the plastic - but it will affect the magnetic strip on the back. It's far safer to get a damaged card replaced.

ANSWER: Metal helmets are still in use by professional divers. Many consider the metal helmet to be safer than SCUBA gear.

Even though hydrogen is lighter, helium is safer because it is a zero fire risk whereas hydrogen has a tendency to explode and/or catch aflame when lit, for example the Hindenburg.

It made it safer to work in factories, more factories were created, it is against the law to force children into work, and machines have replaced human jobs.

It was, and still is, a very useful explosive for blowing out tree stumps or splitting large rocks into smaller pieces. It has largely been replaced by safer and easier to handle products.

Helium had valence electron of 2 and filled the most inner ring so it is chemically robust and inert. Outer valence electron ring contain 8 electrons so for Neon is robust as it had 2,8 electrons and Argon had 2,8,8 electrons and fill the outer ring.

oh. by safer sex. safer abilities. & safer people. you know. ;)