Amixture of oxygen, nitrogen and hydrogen gases exerts a total pressure of 85 kpa at 0 degrees celsius .the partial pressure of the oxygen is 20 kpa and the partial pressure of the nitrogen is 50 kpa .what is the partial pressure of the hydrogen gas in this mixtures ?

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

Which symbol can be used to indicate the pressure at which a chemical reaction is carried out? 25°c 2 atm pa

In medium-sized stars such as the sun, nuclear fusion almost always means the fusing of nuclei to form , but larger stars can produce elements as heavy as