2, 4-Dimethylpentane is the c_7 compound that gives 3 signals in the broadband proton decoupled ¹³C spectrum.
This compound is classified as an alkane and it's chemical formula is [(CH3C)2CH]2CH2. It is a hydrocarbon that has no odor. When it is combined with other gas compounds it gives high octane fuel.
If anything but H2O were found, it would be evidence of a chemical change. Therefore, 4 is the only viable evidence that it was a physical change of H2O liquid to H2O gas.
