Each element has a unique name and is represented in the periodic table by a symbol, which most often is based ... The periodic table is composed of vertical columns called groups and horizontal rows called periods. ... Group 7A Halogens. Feb 27, 2014 — Group 17 elements are called halogens because halogen is a Greek word which means 'salt producing'. Halogens include fluorine, chlorine, ... f50e787ee1 attval
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