Options are;
(A) H-O bonds break as H-H and O-O bonds form.
(B) Hydrogen bonds between H2O molecules are broken.
(C) Covalent bonds between H2O molecules are broken.
(D) Ionic bonds between H+ ions and OH− ions are broken.
(E) Covalent bonds between H+ ions and H2O molecules become more effective.
Answer:
B: Hydrogen bonds between H2O molecules are broken.
Explanation:
When water is changing from liquid form to vapour form, it's molecules move at a faster rate. This is because the bonds between the molecules have been broken as a result of the heat that converts the liquid to vapour.
And the type of bond that forms water molecules is hydrogen bonds.
Thus, hydrogen bonds are broken when converting from liquid to vapour phase.