Which Gas is Safer for Inflating Balloons?

Which Gas is Safer for Inflating Balloons

The only gases that can make balloons fly are hydrogen and helium. The so-called hydrogen balloons can float because their density is lower than that of air. In middle school chemistry, we learn about the periodic table of elements, which lists elements in the following order: hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, and so on. From this, we can see that hydrogen (i.e., hydrogen gas) has the lowest density, followed closely by helium (i.e., helium gas), indicating that helium is also a very light gas. Therefore, balloons filled with helium can also float.

Hydrogen is unsafe and prone to explosions, so safety is paramount in settings like kindergartens and weddings. Helium, on the other hand, is not dangerous. To make helium balloons fly longer, a balloon protective liquid can be used. This liquid is first applied inside the balloon, evenly distributed, and then the balloon is inflated, allowing it to stay airborne for a longer time. Alternatively, balloons can be attached to the ceiling using adhesive.

Whether it's aluminum foil balloons, latex balloons, PVC inflatables, or other types of balloons, helium is the safest gas to use. The reason balloons can float is that the gas inside them has a lower density than air. As mentioned earlier, hydrogen has the lowest density, followed by helium, which is also a very light gas. Thus, helium-filled balloons can float as well.

So why is helium considered the safest gas? Helium has a density of 0.1786 kg/m³, meaning that one liter of helium weighs 0.17847 grams. It is the second least dense gas after hydrogen. Therefore, when helium is used to inflate aluminum foil balloons, it allows them to rise into the air.

Helium is a colorless, odorless, and tasteless inert gas at room temperature. Here, we might not yet understand what an inert gas is. The term "inert" originally means "noble" in English, and inert gases are also called "noble gases." The term "inert" implies inactivity, while "noble" suggests exclusivity. These elements are named as such due to their aloof and unreactive nature. Under normal conditions, helium does not react with other elements or compounds, earning it the reputation of being "lazy," which is why it is called an inert gas.

According to the "Balloon Release Management Regulations" issued by the National Meteorological Administration, hydrogen should not be used to inflate balloons; instead, helium should be used. This is because helium is an inert gas that does not burn or explode. However, helium is more than ten times more expensive than hydrogen, leading some vendors to use hydrogen instead of helium to maximize profits. Balloons filled with hydrogen are essentially dangerous "bombs" because when hydrogen mixes with air in certain proportions, even a small spark or static electricity can cause an explosion.