Harmonic melody and something else hold on...checking
Answer: An inorganic acid.
Explanation: An inorganic acid (also called a mineral acid) is an acid derived from one or more inorganic compounds. All inorganic acids form hydrogen ions and the conjugate base ions when dissolved in water. Commonly used inorganic acids are sulfuric acid (H2SO4), hydrochloric acid (HCl), and nitric acid (HNO3). Hope this helps :)
The answer to this item is TRUE. This can be explained through the Graham's law. This law states that the rate at which gases diffuse is inversely proportional to the square root of their densities which is also related to their molecular masses.