An observation balloon was filled with 0.50 atmospheres of Helium, 54.0 mm Hg of Nitrogen, and 0.400 atmospheres of Hydrogen. What pressure in atmospheres was the balloon filled to?

18. use the activity series to predict whether the following synthesis reaction will occur. write the chemical equations for the reaction if it's predicted to occur. (s) + o2(g) -> *note: it is possible.*

Adeuteron, 21h, is the nucleus of a hydrogen isotope and consists of one proton and one neutron. the plasma of deuterons in a nuclear fusion reactor must be heated to about 3.02×108 k . what is the rms speed of the deuterons? express your answer using two significant figures.

Why does a plastic bottle that is sealed at a high altitude change it’s shape when taken to lower altitude