Four gases were combined in a gas cylinder with these partial pressures: 3.5 atm n2, 2.8 atm o2, 0.25 atm ar, and 0.15 atm he. what is the total pressure inside the cylinder? what is the mole fraction of o2 and ar?

Which formula can be used to calculate the molar mass of ammonia (nh3)? molar mass of n + molar mass of h 3 × molar mass of n + molar mass of h molar mass of n + 3 × molar mass of h 3 × molar mass of n + 3 × molar mass of h

Calculate the number of molecules present in 0.750 mol of mgo.

At a certain temperature the rate of this reaction is first order in hi with a rate constant of : 0.0632s2hig=h2g+i2g suppose a vessel contains hi at a concentration of 1.28m . calculate how long it takes for the concentration of hi to decrease to 17.0% of its initial value. you may assume no other reaction is important. round your answer to 2 significant digits.