Answer:
C. naturally uncombined with other elements.
Explanation: Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air.
The electron releases energy.
It’s 5% because without the 5% you wouldn’t make it to 100 equally
Answer:
C) Lighting a matchstick
Explanation:
Mixing an acid and base will cause a neutralization reaction, a type of double displacement.
Photosynthesis is just a series of chemical reactions, but don't deal with the use of O2, but rather it's creation.
Reacting sodium and chlorine would make NaCl in a synthesis reaction.