At what temperature will 7.5 moles of O2 have a volume of 73.1 L and a pressure of 2.3 atm?

If a molecule with a molecular formula of c13h18 is treated with an excess of h2 in the presence of finally divided pt metal under conditions required for maximum hydrogenation of the molecule to give a molecule with a formula c13h24, how many rings are in the molecule?

May someone me with these science questions

Is 9 correct? and can someone me with 10? it’s due tomorrow, you