Perfume evaporating is it a chemical change or physical change

Agas mixture with a total pressure of 745 mmhg contains each of the following gases at the indicated partial pressures: co2, 245 mmhg ; ar, 119 mmhg ; and o2, 163 mmhg . the mixture also contains helium gas. part a what is the partial pressure of the helium gas? phe p h e = nothing mmhg request answer part b what mass of helium gas is present in a 10.2-l sample of this mixture at 283 k ? m m = nothing g request answer

Which statement describes james chadwick’s discovery.

Chromium(iii) sulfate is a transition metal compound containing the metal chromium and the polyatomic ion sulfate. the oxidation state of chromium in this compound is , and the chemical formula of the compound is ( ) . reset next