group 1 elements Flashcards
list 2 properties of alkali metals
-soft (easily cut with a knife)
-low density
-low melting and boiling points compared to other metals
trend within first three in group
less dense than water
what happens to the reactivity as you go down the group?
it increases
what happens to the melting and boiling points as you go down the group?
they decrease
what happens to the atomic mass as you go down the group?
it increases
why does reactivity increase down the group?
the electron is further away from the nucleus as you go down the group as the atom gets bigger due to more shells, therefore the attraction between the nucleus and valence electron is weaker, so the valence electron is more easily lost
what charge do group 1 ions have?
1+
what compounds do group 1 metals react to form?
ionic
reaction with water
metal (s) + water (l) -> metal hydroxide (aq) + hydrogen (g)
how do they react with water
vigorously, from hydrogen and hydroxides, fizzing, moves on surface
what happens to the reaction with water as you go down the group?
more energy is given out by the reaction, it is more violent
reaction with chlorine
metal + chlorine -> metal chloride
how do they react with chlorine?
vigorously
what do group 1 metals form when reacted with chlorine?
white metal chloride salts
what happens to the reaction with chlorine as you go down the group?
it gets more vigorous
reaction with oxygen
metal + oxygen -> metal oxide
sodium reaction with oxygen products
a mixture of sodium oxide and sodium peroxide
potassium reaction with oxygen products
mixture of potassium peroxide and potassium superoxide
why do group 1 metals tarnish in the air?
when they react with oxygen, it forms a dull metal oxide layer
compare group 1 to transition: reactivity
group 1 are much more reactive and react more vigorously
compare group 1 to transition: density
transition metals are much more dense
compare group 1 to transition: strength and hardness
transition metals are much stronger and harder, group 1 are soft and can be cut with a knife
compare group 1 to transition: melting points
alkali metals have much lower melting points
why are they called alkali metals?
they react with water to give alkaline solutions
why is sodium not a good metal for a cooking pot?
it reacts with water to for alkaline solutions which is unsafe in food
what do alkali metals form when reacted with water?
hydrogen gas and a metal hydroxide
why are group 1 metals stored under oil?
prevent them reacting with oxygen and water vapour in the air
what is the type of reaction when a group 1 metal reacts with oxygen?
oxidation
what do the ionic compounds look like that they form?
white solids that dissolve in water to form colourless solutions
what happens to the amount of energy released as you go down the group?
it increases
transition v group 1: colour of compounds
transition-colourful
group 1-white
transition v group 1: ions
transition-different ions
group 1-form 1+ ions
colour of flames when burnt in oxygen (Li, Na, K)
Li-crimson red
Na-yellow-orange
K-purple/purple
words to describe group 1 reactions
very exothermic, violent, explosive
