C) Thermal energy. Your body turns the mechanical energy into thermal energy.
Explanation:
A chemical reaction is one in which a chemical change occurs.
During a chemical change;
- The process is irreversible
- New kinds of matter produced
- There is a change in mass
Based on these premise;
Baking cake batter is a chemical reaction because you cannot reverse the process
Shredding a paper is not a chemical reaction because no new kind of matter is produced.
Twisting of a metal wire is not a chemical reaction
Yellowing of newspaper in sunlight is a chemical change. The process cannot be reversed
Hess' Law of Constant Heat Summation was developed by Germain Henri Hess who lived from 1802 - 1850. This law became important primarily for his thermochemical studies. This law states that the heat released or absorbed in the chemical reaction is unchanged or the same irregardless of how many steps the reactants take in order to convert to products.
This law is not applicable or not helpful in the conversion of diamond to graphite because both are just allotropes of carbon along with C60 (Buckminsterfullerene or buckyball), C540, C70, amorphous carbon, and carbon nanotube.
So basing on my understanding of this so far, an atom is an element that has the same number of protons and neutrons, an ion is an element that has different numbers of protons and electrons, an ion is positive when it has more protons than electrons and negative when it has more electrons than ions .