What is the standard enthalpy of formation of Fe

If 90.0 grams of ethane reacted with excess chlorine, how many grams of dicarbon hexachloride would form

What is the independent variable in this investigation? mass volume sample number substance density

There is one girl i like and i don't know how to tell her that, i have a feeling she knows but if she doesn't i don't want to make a fool out of myself how is one way to boost my confidence on asking her out