(4 marks) .. A hydrogen balloon at the Earth's surface has a volume of 5.0m on a day when the
temperature is 27°C and the pressure 1 atm. What is the mass of hydrogen? The balloon
rises and expands as the pressure drops. What would be the volume of the same number
of molecules of hydrogen at an altitude of 40km where the pressure is 0.33X10 Pa and
temperature is -13°C
(8 marks)​

im not to sure what it is

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary 

graph slopes whilst gas cools, then it is flat whilst conensation to liquid happens, the coolong liquid then graphs as a slope when it solidifies graph is flat

latent heat

small = small current large mag large current