What happens when the chemicals inside an instant cold pack mix together A. the mixture inside the pack gives off coldness
B. the mixture generates static electricity
C. the mixture absorbs thermal energy from the surroundings
D. the mixture releases thermal energy into the surroundings.

the answer is C

Explanation:

there is no such thing as COLD exept absolute ZERO. anything that feels COLD, perse, is just tranfering your thermal energy into it, since it is lacking that energy

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.