In which sample do molecules have the greatest average kinetic energy? a. O2 at 100K or O2 at 200K, why?
b. N2 at 300K or Cl2 at 300K, why?

Can anyone (a-level) a student was analysing a carbonate compound, mco3, containing an unknown group 2 metal, m. the student carried out thermal decomposition on 0.730g of the carbonate and measured the volume of gas produced. mco3 (s) mo (s) + co2 (g) the student collected and measured 120cm3 of carbon dioxide. 1 mol of carbon dioxide occupies 24 000 cm3 under these conditions. calculate the molar mass of the group 2 carbonate and hence deduce the identity of the group 2 metal, m.

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.

Acertain atom has 22 protons and 19 electrons. this atom loses an electron. the net charge on the atom is now 4+1+01-4-. if this same atom with 22 protons and 19 electrons were to gain 3 electrons, the net charge on the atom would be 3+2+02-3-.