Answer:
atomic number
Explanation:
atomic number is the number of protons
In acidic solutions you have H+ but in basic solutions you have OH-.
You need know that for to balance the reaction.
Answer:
<em>The electrons in an atom can only occupy certain allowed energy levels to a lower one</em>, the excess energy is emitted as a photon of light, with its wavelength dependent on the change in electron energy. This is why an atom can only emit specific wavelengths of light and not every possible wavelength.
Elements in the same group have D. Same number of valence electrons.
I think its the mirror because condenser helps in allowing the amount of light to pass.
