Group 7: Reactivity & Electronic Configurations Flashcards
All 4 cards in this deck
What happens to the melting points and boiling points of the halogens going down group 7?
e.g. chlorine → bromine → iodine
They increase — chlorine is a gas, bromine a liquid and iodine a solid at room temperature.
Which two group 7 elements are solids at room temperature?
Iodine and astatine.
True or false? The halogens become more reactive going down group 7.
False. Reactivity decreases down group 7 — atoms have more electron shells, so an electron is gained less easily.
How many electrons does a halogen atom have in its outer shell, and what ion does it form?
Seven. It gains one electron to complete its outer shell, forming a 1− ion called a halide ion, e.g. .