Different elements produce different colors of light when heated because the electrons in these elements have different permissible energy levels. When an element is heated, the electrons inside it become excited and move to an higher energy level from the ground state. When the electrons drop from this higher energy level, they typically emit energy quantum, the color of the light that is observed at this stage depends on difference that exist in the two energy levels.<span />
It actually depends on the percentage of the concentration give. Percentages can be expressed as %mass/mass, %volume/volume or %mass/volume. To keep things simple, let's just assume that it is in %volume/volume. Thus, 13% of 520 mL is pure acid.
Volume of pure acid = 520*0.13 = 67.6 mL
71% of the earth is water and the 29% is continents and islands.
