Answer:
vertical, upright, erect, disinclined.
If you burn a candle, it's mass will decrease. If that's the case you have changed a physical property of the candle.
Burning anything is always a chemical change Gasoline ( a hydrocarbon) burns in oxygen to produce water and carbon dioxide.
It should be 0.25 M. Use the formula C1*V1=C2*V2, for those values, as it is right when it changed colour. Remember to change the if those are not the same (but in your case it is, so no need this time).
C1*V1=C2*V2
C1*27ml=0.55M*12.5ml
C1=(0.55M*12.5ml)/27ml = 0.25M
Please add a picture of what numbers ; )
