48% off (Sale price $312.00, Reg. Price $600.00) :: The Deal$312 for a lego party for up to 10 guests ($600 value) Pizza, drinks, and cupcakes* Paper goods including tablecloths, plates, napkins, and cups* Photos emailed to all guests* Craft activities and materialsFour Things to Know About HeliumOutside of a stack of vinyl harpsichord recordings, nothing says a party like a bundle of helium balloons. Read on to learn more about what’s inside these festive floaters.1. It’s the second most common element in existence, behind hydrogen. Although the universe will never see a shortage of helium, some fear that, based on the current rate of helium use, Earth’s supply may be exhausted in the future. For now, the US is the world’s largest supplier of helium gas.2. Helium is lighter than air. While a liter of air weighs 1.25 grams, a liter of helium weighs just 0.18 grams. This is why a filling a balloon with helium makes it float and why Fred Astaire pumped helium into his shoes before every dance.3. Heed the Hindenburg. Hydrogen is more buoyant than helium, but it’s also highly flammable, making it a risky choice to fill dirigibles. Nonetheless, engineers of the famous Hindenburg blimp filled it with hydrogen instead—a fact that some early studies blamed for the aircraft’s infamous fire. Such claims have since been disputed, however.4. Inhaling helium can change the sound of your voice. Because helium is lighter than air, the speed of sound in helium is much faster than the speed of sound in air. When filled with helium, the vocal tract still remains the same size, so the frequency of the sound waves must increase, resulting in what sounds like a higher pitch. Note: inhaling helium is very dangerous and can lead to lung damage and even death; do not try it at home.
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