You have two balloons of equal volume at room temperature and 1 atm pressure. One balloon is filled with He and the other is filled with H2. Which statement is true about the relative number of gas particles in the two balloons

1. The He balloon has approximately half

the number of particles, since each particle is

only composed of 1 atom.
2. The He balloon has approximately half
the number of particles since each particle
has about twice the mass of H2
3. The H2 balloon has approximately half
the number of particles since each particle
has twice as many atoms.
4. Both balloons have approximately the
same number of gas particles.

Look at the potential energy diagram for a chemical reaction. which statement correctly describes the energy changes that occur in the forward reaction?

An isolated conducting spherical shell carries a positive charge. part a which statement (or statements) about the electric field and the electric potential inside and outside the spherical shell is correct? which statement (or statements) about the electric field and the electric potential inside and outside the spherical shell is correct? electric potential inside the shell is constant and outside the shell is changing as 1/r2 both the electric potential and the electric field does change with r inside and outside the spherical shell electric potential inside and outside the shell is constant, but not zero electric potential inside the shell is constant and outside the shell is equal to zero electric field inside and outside the shell is constant (does not change with the position r), but is not equal to zero electric field inside and outside the shell is changing as 1/r (where r is the distance from the center of the sphere) electric field inside is equal to zero and outside the shell is constant, but not zero electric potential inside the shell is constant and outside the shell is changing as 1/r electric field inside and outside the shell is changing as 1/r2 electric field inside is equal to zero and outside the shell is changing as 1/r2 electric field inside and outside the shell is zero electric field inside is constant and outside the shell is changing as 1/r

In science and physics what is the standard unit of measure for speed?