Which item below is an example of a mixture. A) Distilled Water

B) A bottle of hydrogen peroxide h2o2

C) Seawater

D) Liquid CO2

C. sea water

Explanation: basically when you see words that look like someone sneezed and whatever they managed to type (example: Copernicium) just go ahead and eliminate it when it comes to mixtures. Distilled water was there to trick you. Always look for the distilled part, that means it is pure, and therefore not a mixture.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.