Do all gases ,eg CO2, O2, H2, expand at the same rate when heated?

Question

Do molecular weight and electron number play a role in the Brownian movements?

Answer 1

There are a variety of answers because there are different interpretations of what expand means and heated means.
Using the Ideal gas laws PV=NKT so if there are the same number of molecules in a volume the pressure will only depend temperature and will be independent of the kind of gas. If the temperature is increase to t' keeping the pressure constant (balloon) the amount the balloon expands will be the same for all. However if the expansion is in a vacuum the the speed of the molecule is what will mater. The kinetic energy of the molecule 1/2mv^2=/2kt so the lighter ones will move faster, and expand faster.
If you mean adding the same amount of heat, not raising to the same temperature, you will need to also consider the heat capacity of the gas which will depend on the molecular composition.

Answer 2

No. For an ideal gas, the thermal energy is Eth =3kT/3, which can be equated to the molecular kinetic energy Ekin = mv^2/2 to deduce the molecular velocity. Heavier molecules move slower, so the rate of expansion is not the same. Real gasses have intermolecular forces that modify the result, but because the interactions are weak in the gas state, the same end result is obtained.
Edit Ken B is correct about the equilibrium state, but not about the molecular kinetics to achieve the equilibrium state.

Answer 3

In the real world, no. But at low high temperatures (above 50 K) and low pressures (<10 bar) most gasses will act as if they are ideal. Thus they will closely follow the ideal gas law (PV=kT) and assuming that pressure is held constant, each will expand in nearly identical ways.

Molecular mass and polarity will impact the expansion more than any other factor (at high temps and low pressures), but as pressure increases, molecular radius becomes a larger factor

Answer 4

becaz the main needed diffrence between suitable gasoline and authentic gasoline,is the stress between molcules,and idal gasoline has no stress. then H2 ,becaz of much less stress is right than yet another

Answer 5

molecular weight plays a important role.greater no of molecules ,greater will be browian movement.

Answer 6

The simple answer is no. I am not a chemist but I know that the number of BTU's to turn water to steam is different that what it takes to change liquid ammonia to vapor.

Answer 7

No, they all have different molecular structures and will therefore react differently.

Answer 8

nope mol.wt. and electrons matters

Answer 9

but i n my chemistry book it is written the do

Answer 10

No..