floating water baloons
Liquid Helium is colder than Liquid Hydrogen.
A little bit of yes and a little bit of no. There are two issues: Between its boiling point (about 4.2 K) and its "lambda point" (around 2.2 K), liquid helium-4 is a normal liquid. Below the lambda point, however, helium-4 becomes superfluid. The isotope helium-3 also has a superfluid phase, but it occurs at a significantly lower temperature. So whether the answer to your question is "yes" or "no" depends on which isotope of helium you're talking about, and exactly what the temperature is.
balloons and some times hot air balloons dozens of industrial and scientific uses.
helium or vapour
The helium and liquid hydrogen won't mix. The liquid nitrogen is not cold enough to cause the helium to liquify, and the helium is an inert gas and will not react with the nitrogen.
There is no word equation, except that helium will exist as liquid phase in liquid helium
Liquid Helium is colder than Liquid Hydrogen.
Yes. conversion of liquid helium to gaseous helium is a physical property
The liquid helium would boil and evaporate.
Above -268.93 °C, helium is gas. Below -268.93 °C, helium is liquid. Helium cannot exist as solid.
Yes it is. Helium will be liquid below -268.93 °C
what is the density of helium at room temperature?
Liquid helium in the helium I phase boils at about 5 K, lower than any other substance. (Liquid helium in the helium II phase does not boil, it simply evaporates. Helium is truly weird stuff at very low temperatures.)
Litre or cubic meter for helium as a gas; litres for helium as a liquid.
Every liquid, with the single exception of liquid helium, will eventually freeze if it gets cold enough. Helium, however, does not freeze.
Liquid helium is a lot colder than liquid nitrogen.
Liquid helium is used to cool the superconducting electromagnets.