halogens
... -219.62 °C (53.530006 K, -363.31598 °F) Boiling Point: -188.14 °C (85.01 K, -306.652 °F) Number of Protons/Electrons: 9 Number of Neutrons: 10 Facts Date of Discovery: 1886 Discoverer: Joseph Henri Moissan Name Origin: From the Latin word fluo (flow) Uses: Refrigerants Obtained From: mineral fluorite Name: Chlorine Symbol: Cl Atomic Number: 17 Atomic Mass: 35.4527 amu Melting Point: -100.98 °C (172.17 K, -149.764 °F) Boiling Point: -34.6 °C (238.55 K, -30.279997 °F) Number of Protons/Electrons: 17 Number of Neutrons: 18 Facts Date of Discovery: 1774 Discoverer: Carl Wilhelm Scheele Name Origin: From the Greek word khlôros (green) Uses: Water purification, bleaches Obtained From: Salt Name: Bromine Symbol: Br Atomic Number: 35 Atomic Mass: 79.904 amu Melting Point: -7.2 °C (265.95 K, 19.04 °F) Boiling Point: 58.78 °C (331.93 K, 137.804 °F) Number of Protons/Electrons: 35 Number of Neutrons: 45 Facts Date of Discovery: 1826 Discoverer: Antoine J. Balard Name Origin: From the Greek word brômos (stench) Uses: Poisonous Obtained From: Sea Water Name: Iodine Symbol: I Atomic Number: 53 Atomic Mass: 126.90447 amu Melting Point: 113.5 °C (386.65 K, 236.3 °F) Boiling Point: 184.0 °C (457.15 K, 363.2 °F) Number of ...