Question

the elements in group 1 and 17 in the third period are​

Answer 1

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Group 1 is hydrogen....

Group 17 is chlorine....

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Answer 2

Answer:

Group 1-- hydrogen , lithium , sodium, potassium, Rubidium ,Cesium ,Francium

group 17 -- fluorine, chlorine, Bromine, iodine, astatine , astatine