Answer : The molecular weight of a gas is, 128.9 g/mole
Explanation : Given,
Density of a gas = 5.75 g/L
First we have to calculate the moles of gas.
At STP,
As, 22.4 liter volume of gas present in 1 mole of gas
So, 1 liter volume of gas present in
mole of gas
Now we have to calculate the molecular weight of a gas.
Formula used :

Now put all the given values in this formula, we get the molecular weight of a gas.


Therefore, the molecular weight of a gas is, 128.9 g/mole
I am going to say C. it has to do with the angles
<span> The production of absorption and emission lines . The first theory of the atom to provide an explanation of </span>hydrogen's<span> observed </span>spectral lines<span> those two energy levels, the electron </span>can<span> exist only in </span>certain<span> sharply defined . The </span>number<span> of protons in the nucleus of an atom determines the </span>element<span> that </span>