Why do different chemicals emit different colors of light, and why is the color emitted specific to that chemical?

Every chemical is made up of atoms and each atom has one or more electrons surrounded its nucleus. The electron emits light after changing from a high energy state o to a lower energy state which is known as transition. The color of this light is unique to each element because each atom of a particular element has a different transition energy.

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.

i think   the answer is c hope i'm right