# please explain?

When you buy a helium-filled balloon, the seller has to inflate

it from a large metal cylinder of the compressed gas. The helium

inside the cylinder has energy, as can be demonstrated for example

by releasing a little of it into the air: you hear a hissing sound,

and that sound energy must have come from somewhere. The total

amount of energy in the cylinder is very large, and if the valve is

inadvertently damaged or broken off, the cylinder can behave like a

bomb or a rocket.

Suppose the company that puts the gas in the cylinders prepares

cylinder A with half the normal amount of pure helium, and cylinder

B with the normal amount. Cylinder B has twice as much energy,

and yet the temperatures of both cylinders are the same. Explain, at

the atomic level, what form of energy is involved, and why cylinder

B has twice as much.

### 1 Answer

- Anonymous1 month ago
The energy can be represented by either half of the equation

pV = nRT

In cylinder B you have doubled "n", and so you have doubled the energy (R, T constant).