Groups Flashcards
what are group 1 metals also called?
alkaline metals
how many electrons do group 1 elements have in their outer shell?
1
what are the general trends going down group 1?
reactivity INCREASES going down the group
atomic radius INCREASES going down the group
melting/boiling point DECREASES going down the group
hardness DECREASES going down the group
what makes elements more reactive?
a further distance from the attraction of the nucleus
more shielding (when the attraction of the nucleus is blocked by other electrons)
what are group 7 elements also known as?
the halogens
what are the general trends for group 7 elements going down the group?
reactivity DECREASES as you go down the group
boiling/melting points INCREASE going down the group
what do all halogens exist as?
diatomic particles (in pairs)
why does reactivity increase going down group 1 but decreases going down group 7?
-in group 1 the elements are trying to lose one electron
-as the number of electron shells that an element has increases going down the group this means there is more distance and shielding
-this makes it much easier to lose an electron
-on the other hand group 7 elements must gain an electron to complete their outer shell
-the atomic radius also increases going down this group so theres more distancing and shielding
-this weakens the attraction from the nucleus so makes it harder to attract an electron
why does the boiling/melting point of halogens and noble gases increase going down the group?
-the intermolecular forces between molecules increases as the molecules are getting larger so makes it harder to overcome them
what do the halogens fluorine, chlorine, bromine and iodine look like?
fluorine- is a pale yellow but almost colourless very poisonous and reactive gas
chlorine-is green/ yellow poisonous dense gas
bromine-is a red/brown volatile (turns into a gas easily) and poisonous liquid
iodine- is a dark grey solid or a purple vapour
what are group 0 elements also called?
noble gases
what do all noble gases have in common?
they have a full outer shell making them very unreactive
what do all noble gases exist as?
monatomic particles (by themselves)
what are the general trends for group 0 as you go down the group?
reactivity stays the same but very low
boiling points increase as you go down the group
density INCREASES going down the group
why are noble gases gases at room temperature?
they have weak intermolecular forces that break with little energy
w
why could noble gases not have been discovered earlier?
they are colourless and odourless as well as being unreactive so could not be easily seen
why would argon be useless in a party baloon?
its denser than air so it would just fall to the ground
