Recall all the models you described in task 1. Think about the results each model would predict for the experiment with hydrogen gas. Which models of the atom does the experimental evidence support? Explain why these models are compatible with the experimental results.

Rutherford's Atomic Model : "The model described the atom as a tiny, dense, positively charged core called a nucleus, in which nearly all the mass is concentrated, around which the light, negative constituents, called electrons, circulate at some distance, much like planets revolving around the Sun."

Dalton's Atomic Model : "He defined an atom to be a ball-like structure, as the concepts of atomic nucleus and electrons were unknown at the time."

Thomson's Atomic Model : "Thomson's experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. Thomson proposed the plum pudding model of the atom, which had negatively-charged electrons embedded within a positively-charged "soup.""

A gas discharge tube consists of a gas-filled tube fitted with a metal electrode at each end. In this case, the gas used is hydrogen. An electric current is passed through the tube. The electrons in the hydrogen absorb energy from the electric current and get excited to a higher energy level. As the electrons return to their original energy state, called the ground state, they emit light of a specific color. The color of the light depends on the amount of energy that it carries. This energy is the difference in energy of the excited state and the ground state. Particles of different gases emit light carrying different amounts of energy and, as a result, different colors. Hydrogen emits four visible colors of light.