In terms of macromolecules, needed and utilized by organisms to carry out essential metabolic chemical reactions and for maintaining structure would be Lipids.
Lipid based molecules or Fats tend to store the most energy, as breaking chemical bonds connecting fatty acid chains of long hydrocarbons releases quite a bit of energy.
Answer:
The correct answer is d. hydronium ion.
Explanation:
Hydronium ion is a positively charged molecule that has three hydrogen atom bonded with an oxygen atom. Hydronium ion is formed when the water molecule gains an extra H+ ion from somewhere.
This H+ ion easily form bonds with one of the lone pairs present on the water molecules. H2O is also a polar molecule and has a partially positive charge due to which the extra H+ ions get attracted to the negative pole of water and make hydronium ion. Therefore the correct answer is d.
Stars Like the Sun. When the core runs out of hydrogen fuel, it will contract under the weight of gravity. ... The upper layers will expand and eject material that will collect around the dying star to form a planetary nebula. Finally, the core will cool into a white dwarf and then eventually into a black dwarf.