Experiment 1: Lithium in Water
Demonstration of Alkali metal and water reaction
Experiment Description (should be at least more than 200 words)
This experiment demonstrates what happens when lithium, an alkali metal, is placed in water. The experiment goes as follows, lithium is to be removed from a lithium ion battery and separating the two metals inside, lithium as the cathode and typically graphite as the anode. The lithium will be separated and placed in water which will subsequently fizzle and explode. This happens scientifically because lithium is an alkali metal, which are the most reactive metals. These metals are incredibly reactive because they only have one valence electron, making them the most electropositive elements (electropositivity describes how easily an atom gives away an electron). Once placed in the water the very electropositive lithium reacts with the very electronegative oxygen to form lithium hydroxide, Li(s) + H2O(l) → LiOH(s) + H+(g). The reaction forms LiOH (lithium hydroxide) and not Li2O (lithium oxide) because the hydroxide is more stable and requires extra energy to remove the final hydrogen from the oxygen making the product. This is why when lithium is added to cold water it forms lithium hydroxide and when lithium is exposed to steam it forms lithium oxide, the extra energy comes from the heat of the steam. The reaction also has a hydrogen ion as the other product, which is why the reaction fizzles when first placed in the water; the lone hydrogen ions, H+(g), bond with each other to form hydrogen gas, H2(g). The reaction releases heat because energy is released when bonds are formed, the lithium with the oxygen, and this heat causes the hydrogen gas to ignite, which is the source of the spontaneous explosion. The residual lithium hydroxide, LiOH, remains in the water after the experiment is over. A recent study has shown that fractions of a second after an alkali metal makes contact with the water it expands into protruding spikes. This is due to the loss of electrons in the metal, making it very positively charged for a moment and during this moment it expands and creates protruding spikes from the repelling forces, causing the reaction to occur faster because the metal has a larger surface area. But this information is incredibly hard to capture and not very important to the understanding of the process.
Notes:
What’ll happen:
Place lithium from lithium ion battery to display reaction
Science:
This happens because…
Alkali metals are the most reactive metals due to their atomic structure
Only have 1 valence electrons making them very reactive
Once in water the very reactive metal reacts with the also very reactive oxygen forming metal hydroxide and hydrogen gas
Show formula
It forms a hydroxide and not an oxide ion because the hydroxide is more stable and would require extra energy to make it into the metal oxide
Li(s) + H2O(l) → LiOH(s) + H+(g)
That is why in cold water metal hydroxides are created but in steam metal oxides form
The reaction fizzles because that is the hydrogen gas leaving the system
The newly created gas ignites because heat is released from the exothermic reaction meaning that the reaction is thermodynamically favorable, which is why it happens spontaneously
Causing boom
Leaving a residual metal oxide at the bottom of the water
Extra info
New information which isn’t commonly taught had been found
Due to the loss of electrons the metal becomes very positively charged for a moment and during this moment it expands and creates protruding spikes from the repelling forces of the charge
Instructions
Start with a lithium ion battery and glass of water
Tools used: pliers, tweezers
Remove the lithium from the battery with tools
Remove outside plastic wrap
Peel back steal casing to remove top plate
Roll back the casing exposing the center
Wait to unravel core because it will immediately react with the air
Place in water and observe
