The easiest way is to fill two very light globes, each with a different gas.
Blow globe 1 with gas from the cylinder marked with label 1, and blow glove 2 with gas from the cylinder marked with label 2.
If a globe ascends in the air, it is because its gas is less dense than air.
Inflate the globes quite enough to be sure that the mass of the rubber of the globe is not important relative to the mass of gas and so it does not change the results. If you obtain a result where the globe does not have a cliea ascending or descending motion, you can inflate more the globe and it shouuld start to rise if the gas really is less dense than air.
Vt = Vboat - Vriver
Vt = 18 - 2.5 = 15.5 m/s
If the boat's direction is the same as the water, you sum the velocities of the river and the boat .
Answer : Noble Gases do not readily form compounds because they are chemically stable with 8 valence electrons.
Explanation :
Noble gases are the chemical elements that are present in group 18 in the periodic table.
The elements are helium, neon, argon, krypton, xenon and radon.
They are chemically most stable except helium due to having the maximum number of 8 valence electrons can hold their outermost shell that means they have a complete octet.
They are rarely reacts with other elements to form compounds by gaining or losing electrons since they are already chemically stable.
Hence, the noble Gases do not readily form compounds because they are chemically stable with 8 valence electrons.
