Group one/alkali metals Flashcards
(14 cards)
Which group of the periodic table will you find the alkali metals?
Group one
What are the names of all the metals in group one?
Lithium sodium, potassium, rubidium, caesium and francium
Describe the element lithium
Appearance = black and shiny
Appearance when freshly cut = white and oxidising
Hardness = quite soft like cheddar
Observations with water = effervescence, fizzes in the water - releasing steam
Does it ignite = no
Observations of solution when universal indicator is added = goes blue - alkaline solution
Observations when the gas produced is tested with a lit splint = squeaky pop hydrogen is released
Products = Lithium hydroxide
Describe the element sodium
Appearance = light grey matte
Appearance when freshly cut = white oxidising to grey
Hardness = quite soft like Adam or soft cheddar
Observations with water = exothermic effervescence, moves more than lithium, turns into a small ball
Does it ignite = no
Observations of solution when universal indicator is added = girls navy blue alkaline solution
Observations when the gas is produced and tested with a lit splint = squeaky pop hydrogen
Products = sodium hydroxide
Describe the element potassium
Appearance = dark grey black
Appearance when freshly cut = light shiny oxidisers to grey
Hardness = very soft like Brie
Observations with water = ignites, crackles, more effervescence, moves much faster, bounces off the sides of container
Does it ignite = Yes produces a purple pink lilac flame
Observations of solution when universal indicator is added = dark navy blue alkaline solution
Observation when the gas produced is tested with a lit splint = squeaky pop hydrogen is released
Products = Potassium hydroxide
What is the reactivity trend between lithium sodium and potassium?
It increases
Why are all of the alkali metals stored under oil?
So they don’t react with the oxygen air in the container
The reactions from caesium and rubidium
Sodium reacts explosively immediately with water forming sodium hydroxide and hydrogen gas. The reaction is exothermic producing significant heat and causing the water to boil. The release of hydrogen gas can also ignite into a violet flame and cause a further explosion.
Why are there no videos of Francium reacting with water?
Because it would be impossible to collect quickly enough or not to react with the air and it will be too dangerous to add with water.
Put the alkali metals in order of reactivity starting with the least reactive
Lithium, sodium, potassium, rubidium, caesium
What is the reactivity role of group one?
As you go down the group, the metals will increase in reactivity.
What are the two products of the reaction between lithium and water, sodium and water and potassium and water?
Lithium hydroxide plus hydrogen
Sodium hydroxide plus hydrogen
Potassium hydroxide plus hydrogen
Why are the group one metals called the alkali metals?
Because they are alkaline solutions
Describe a test for hydrogen gas
The squeaky pop test, you contain the gas and then react it with a flame to see if it reacts and makes a pop.
