Answer:
The red dot represents the melting point of the element, which as stated is approximately 19.9 degrees Celsius and how long it took for the heat to properly completely dissolve it.
The question kind of answers itself however, is there a way to re-word it or is there a different answer you're looking for?
Molecule, a group of two or more atoms that form the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance.
While Atoms are single neutral particles,
Molecules are neutral particles made of two or more atoms bonded together.
Exaplmes for molecules
H2O (water)
N2 (nitrogen)
O3 (ozone)
CaO (calcium oxide)
C6H12O6 (glucose, a type of sugar)
NaCl (table salt
And examples for atoms
Neon (Ne)
Hydrogen (H)
Argon (Ar)
Iron (Fe)
Calcium (Ca)
Deuterium, an isotope of hydrogen that has one proton and one neutron.
Plutonium (Pu)
F-, a fluorine anion.
it would be A ,inorganic Compound
Limiting reactant in this experiment would be Magnesium since it will run out first