2006 38th IChO Prep Test Answers EnglishProblem 1 A brief history of life in the universe1-1 T = 1010 112 = 1010 K 10 billion degrees1-2 T = 1010 18012 = 07 x 109 ≈ 109 K 1 billion degrees1-3 t = 10

a) Molecules in space can be excited to higher energy levels by absorbing light from stars or other sources. b) When these excited molecules return to lower energy levels, they release energy in the form of photons, which can be detected as spectral lines. c) The frequency and wavelength of these lines can provide information about the composition and conditions of the interstellar medium. d) Different molecules have different energy level structures and therefore produce different spectral lines, allowing for identification and analysis of specific molecules. e) The Doppler effect can also be observed in these spectral lines, providing information about the velocity and motion of the interstellar medium. f) Spectroscopy is a powerful tool for studying the chemical and physical properties of the universe