Alchemists used science together with magic to accomplish tasks.
Answer:
Explanation
To get a mole of a compound just add up the molar mass
For example: O2
1 mole of oxygen is 16g
1 mole of O2= 32g
You can find the molar mass of each individual element on the periodic table of elements
A reaction that is spontaneous means that it can produce products without the supply of energy. The total energy from the reactants reached the activation energy that allow the reaction proceed. An example of this is the decay of a diamond into graphite occuring readily.
Answer: option A. the colors absorbed when an element gains energy.
Justification:
The electromagnetic waves, visible light included, consists of a gamma of waves with different frequencies and wavelengths.
The visible light can be decomposed in a set of series of lines of light with different frequencies and that decomposition is what a spectrum of light is. Each series correspond to a color.
The atoms can absorb and emit photons. That is, atoms can absorb and release energy.
When the atom abosorbs a photon an electron gets excited ( the electron gains energy).
The light absorbed, then, corresponds to color absortion, and the spectrum of absortion is the colors absorbed by the atom when its electrons gain energy by the absortion of photons (light).