The given question is incomplete. The complete question is:
The combustion of propane (C3H8) in the presence of excess oxygen yields 
and 
When only 2.5 mol of 
are consumed in order to complete the reaction, ________ mol of are produced.
Answer: Thus when 2.5 mol of are consumed in their reaction, 1.5 mol of are produced
Explanation:
The balanced chemical equation is:
According to stoichiometry :
5 moles of produce = 3 moles of
Thus 2.5 moles of will produce = 
moles of
Thus when 2.5 mol of are consumed in their reaction, 1.5 mol of are produced
N = PV = (190 atm)(35 L) = 260 moles of gas RT (0.0821 L.atm/mol.K)(315 K)
It might be c, because he came up with the plum pudding model. or it might be that atoms of the same element are identical, but that's not true cuz ions are different and isotopes are different.
Metal period- Reactivity Gets smaller as you move from left to right.
Group- Reactivity gets bigger as you move down a group.
It is option A 4s cause n=4, l=1 this is 4s orbital
