Which statements are true?

check all that apply.

a. the temperature of a substance increases as heat is added, unless there is a phase change.
b. the temperature of a substance does not change during a phase change.
c. as heat is added to a substance, the temperature goes down.
d. the temperature always increases as heat is added to a substance.

Elements that do not have full outer electron shells will donate, share, or take electrons from other atoms. choose the items that have the correct binary ionic formula.

Look at the spectrums of a star moving towards earth and a motionless star. which of these is a correct inference that can be draw from the observation of the two spectrums? (2 points) the spectrum of a motionless star is difficult to be viewed separately using oridinary telescopes. the spectrum of a motionless star is identical to the spectrum of a star which moves towards earth. the spectrum of a star shifts towards the red region when the star moves towards earth. the spectrum of a star shifts towards the blue region when the star moves towards earth.

If 22.5 liters of oxygen reacted with excess of hydrogen, how many liters of water vapor could be produced?