Rank the given compounds on their relative acidity.

Question

Here was the order I thought it was but it turned out to be wrong. (i based it based off of sp being most acidic and sp3 being least acidic)

STRONGEST
HC(triple bond)C-CH3
H2C=CH2
CH3NH2
H2O
CH4--> WEAKEST

and then I looked up the actual pka values and got the following order but it was still wrong...

HC(triple bond)C-CH3 --> STRONGEST
CH3NH2 pka 10.58
H20 pka 15.74
H2C=CH2 pka 44
Ch4 pka 50 ---> WEAKEST

please help I am really confused
Thanks :)

Answer 1

The correct order is:
STRONGEST
HC(triple bond)C-CH3
CH3NH2
H2C=CH2
H2O
CH4--> WEAKEST