Answer:
a process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction
A the solid.
it’s solid because solid is harder than gas and liquid which makes it a greater structure
Answer:

Explanation:
At constant pressure Thermal energy always moves from a greater energy level to a lesser energy level, laws of thermodynamics prove that.
Nature always likes to attain equilibrium either it's movement of heat energy or flow of water from higher region to lower region. The first and second law of thermodynamics are profe of that, the first law says that the total energy of universe is Constant. Energy can not be destroyed it always changes from one form to another, by work and heat. The second law explains why thermal energy moves from a greater energy level to a lesser energy level, it deals with the change in entropy of a system and surrounding and states heat flows from hot environment to cold environment.
<em><u>Thanks for joining brainly community!</u></em>
Answer:
B- Sodium loses an electron.
D- Fluorine gains an electron.
Sodium is oxidized.
Explanation:
The reaction equation is given as:
Na + F → NaF
In this reaction, Na is the reducing agent. It loses an electron and then becomes oxidized. By so doing, Na becomes isoelectronic with Neon.
Fluorine gains the electron and then becomes reduced. This makes fluorine also isoelectronic with Neon.
This separation of charges on the two species leads to an electrostatic attraction which forms the ionic bonds.
Answer:7 atom of carbon+5atom of hydrogen +3atom of nitrogen +6 atom of oxygen =21