halogens Flashcards
can you name two patterns of the halogens?
the substances get darker as you go down the group and fluorine, chlorine are gases, bromine a liquid and iodine a solid
what group are the halogens in?
7
what is the trend of melting and boiling points of the halogens?
as you go down the group, they both increase
why is fluorine a gas whilst iodine is a solid at room temp?
this is because the fluorine’s boiling point is lower than room temp and iodine’s melting point is higher than room temp keeping it solid
what is the trend of reactivity in group 7?
it decreases as you go down the group
how do group 7 elements react?
they react by pulling electrons off of other atoms
why does the reactivity of atoms in group 7 decrease?
since the last shell is further from the nucleus it has a weaker pull on the last electron it is trying to attract.
what happens when you react an alkali metal and a halogen?
it forms a salt, (e.g.) sodium + chlorine = sodium chloride
what is a rule for naming compounds made from metals and non metals?
you start with the name of the metal then the non metal
how do you balance equations?
you have to have the same atoms on both sides of the equation
Can you balance this equation “K + Br2(small 2) = KBr”?
K + br2 = KBr2
What can some of the halogens be used for?
swimming pools, toothpaste, drinking water, table salt
