group 7 Flashcards
all elements in group 7 are ____
non-metals
how many electrons in outer energy levels of group 7?
7
how do two atoms of a group 7 element react?
covalent bond by sharing 1 electron
what does every group 7 element form?
a diatomic molecule consisting of two atoms sharing an electron.
two atoms joined by a covalent bond
what are group 7 elements known as?
halogens
how do group 7 elements form covalent compounds?
when reacting with other non metals
what is a covalent bond?
pair of electrons shared between the two atoms
what do chlorine and hydrogen both require?
1 outer electron to achieve a full outer energy shell by forming a covalent compound. (hydrogen chloride)
what happens when halogens react with metals?
they form ionic compounds. halogen gains 1 electron from metal to achieve a full outer shell. now has an overall charge becoming an ion. forming an ion with a negative 1 charge
what happens when chlorine and lithium (metal) react?
lithium has 1 electron in its outer energy level. lithium gives its electron to chlorine to both achieve a full outer energy level
what is the negative electron attracted to?
the positive charge in the nucleus
what happens to the reactivity as we go down group 7?
it decreases
why does the reactivity decrease as we go down group 7?
the distance between the nucleus and outer electron increases and gets further. this means outer electrons are less attracted ton a positive nucleus.
more electrons in internal energy levels that repel outer electrons. shielding. attraction between electrons and nucleus decreases (get less reactive)
A _______ _______ halogen can _______ a ________ reactive halogen from an ________ solution of its salt
more reactive halogen can displace a less reactive halogen from an aqueous solution of its salt
