Because it has mass. It may be lighter THAN AIR, but that does not mean it is weightless. Even cells have weight.
Helium is the second lightest element on the periodic table, with an atomic number of 2 and an atomic weight of approximately 4.0026 atomic mass units.
Helium balloons float down due to the weight of the balloon being greater than the lift force generated by the helium inside. As the helium inside the balloon slowly leaks out over time, the lift force decreases, causing the balloon to float down.
The rate of effusion of sulfur dioxide is slower compared to that of helium. This is because sulfur dioxide is a heavier molecule than helium, so it moves through a small opening at a slower pace. Helium, being a lighter gas, effuses faster due to its lower molecular weight.
It will take helium gas (He) less time to diffuse than sulfur dioxide gas (SO2) due to its lower molecular weight. Diffusion rate is inversely proportional to the square root of molecular weight, so helium will diffuse faster than sulfur dioxide. Therefore, helium will likely diffuse from the container in less than 20 seconds.
Helium has 2 protons, 2 neutrons and 2 electrons. The symbol for helium is He and the atomic number is 2.
Helium's atomic weight = 4 amu
The weight of helium is very light, as it is one of the lightest elements on the periodic table. Helium has a very low density and weight compared to other elements.
Helium atom has 2 protons and 2 neutrons (that accounts for its atomic weight). The atomic weight of helium is 4.00260
4.002602 g/mol
The atomic weight of helium is 4,002602(2).
No, helium has weight, but it rises when its in an expandable container such as a balloon because it is lighter than the nitrogen rich atmosphere but inside of a rigid container the helium can only add weight. (see the mythbuster's episode about the helium football)
Using helium in tires would have a minimal impact on the weight of a semi-trailer. Helium is much lighter than air, but the amount of helium in the tires is very small compared to the overall weight of the trailer, so the difference in weight would be insignificant.
To convert grams to moles, divide the given mass by the molar mass of helium. The molar mass of helium is approximately 4g/mol. Therefore, 26.7kg of helium is equal to 26,700g, which would be 6,675 moles of helium.
To weight a helium balloon, you can attach small weights to it until it stays grounded. By adding enough weight to counteract the lifting force of the helium, you can measure the weight of the balloon.
Helium has a standard atomic weight of 4.0026 atomic mass units (amu).
The only element helium makes up is helium. Atomic number: 2 Atomic weight 4.00260 u (avg)
The density of helium is approx. 0,9 g/L.