Ethanol is C2H5OH. Burning it produces 2 CO2 + 3 H2O. Ratio of H2O to CO2 is 3/2 = 150%.
Octane is C8H18. Burning it produces 8 CO2 + 9 H2O. Ratio of H2O to CO2 is 9/8 = 112.5%.
In the case of ethanol, more of the gases in the exhaust are carbon and less of them are hydrogen, when compared to octane, which is fairly representative of gasoline.
So, yes, ...
There are a ton of different factors to take into consideration here. Lets make sure we keep net GHGe and tailpipe GHGe separate here.
Net GHGe: Since 2015, satellite observation as well as international agriculture reporting data have started to show that the original assumptions surrounding Indirect Land Use Change (ILUC) for generation I and ...
I don't know about per km, but this article has some info:
This calculator has some info showing the different CO2 Emmissions of petrol vs ethanol: