Answer:
all pure substance are molecules
ASAP stands for as soon as possible
Geiger–Marsden experiment(s)<span> (also called the </span>Rutherford gold foil experiment<span>) were a landmark series of experiments by which scientists discovered that every </span>atom<span> contains a nucleus where its positive charge and most of its mass are concentrated. They deduced this by measuring how an </span>alpha particle<span> beam is scattered when it strikes a thin metal foil. The experiments were performed between 1908 and 1913 by </span>Hans Geiger<span> and </span>Ernest Marsden<span> under the direction of </span>Ernest Rutherford<span> at the Physical Laboratories of the </span>University of Manchester<span>.</span>
The molar mass of the gas : 18 x 10⁻³ kg/mol
<h3>Further explanation</h3>
Given
An unknown gas has one third the root mean square speed of H2 at 300 K
Required
the molar mass of the gas
Solution
Average velocities of gases can be expressed as root-mean-square (V rms)
T = temperature, Mm = molar mass of the gas particles , kg/mol
R = gas constant 8,314 J / mol K
v rms An unknown gas = 1/3 v rms H₂
v rms H₂ :
V rms of unknown gas =
Noun!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!