14. Which type of bond is formed when an ammonia molecule accepts a proton?
1) electrovalent
2) ionic
3) coordinate covalent
4) metallic

dative covalent bond

Explanation: one hydrogen ion is transferred from HCl to the lone pair on NH3 . This particular hydrogen only has its nucleus transferred—its electrons remain with chlorine. So, the bond between this particular hydrogen atom and the central nitrogen is a dative covalent bond.

chemical energy is stored in the chemical bonds of atoms and molecules. it can only be seen when it is released in a chemical reaction. when chemical energy is released, the substance from which the energy came is often changed into an entirely different substance.

this chemical reaction releases energy in the form of light and heat. chemical energy is the potential energy stored in the arrangement of atoms within molecules. breaking chemical bonds requires energy, while forming new chemical bonds releases energy.

the atp molecule can store energy in the form of a high energy phosphate bond joining the terminal phosphate group to the rest of the molecule. in this form,energy can be stored at one location, then moved from one part of the cell to another, where it can be released to drive other biochemical reactions.

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.