Its an ore of uraninte i think.
A pure substance has a constant composition and cannot be separated into simpler substances by physical means. There are two types of pure substances: elements and compounds. Elements: are pure substances made up of only l type of atom. Atoms of the same element are identical in properties.
0.500 moles is roughly .5*6.022*10^23=3.011*10^23 atoms. This is independent of STP.
According to the kmt pressure is directly proportional to the number of collision between particles
A 3.1 L sample of hydrogen <u>d. contains the same number of molecules</u>
as 3.1 L of carbon dioxide at the same temperature and pressure.
This is the fundamental principle of <em>Avogadro’s hypothesis</em>: equal volume of gases at the same temperature and pressure contain the same number of molecules.
The sample of carbon dioxide has a <em>greater mass</em>, a <em>greater number of atoms</em>, and a <em>greater density</em>, than the sample of hydrogen.