Group 1 - The Alkali Metals (2) Flashcards
The melting and boiling points are very low for metals and get __________ as you go down the group. The densities tend to increase but not as tidily as the noble gases
Lower
Lithium, sodium and potassium are all _______ dense than water
Less
These metals are all very reactive and get more reactive as you go ________ the group
Down
To make sure that they don’t react with oxygen or water vapour in air, they are stored under ______
Oil
All of the alkali metals react with water to produce a ________ ______________ and ____________
Metal hydroxide and hydrogen
Therefore:
sodium + water —————> sodium hydroxide + hydrogen
The main difference between the reactions with water is how ________ they happen
Fast
When sodium reacts with water, a white trail is produced this is …
Sodium hydroxide
What happens when sodium reacts with water (detailed)
It floats in the water because it’s less dense.
It melts because its melting point is low and a lot of heat is produced
Because of the way the hydrogen is given off - the sodium is pushed around the surface of the water
What happens when lithium reacts with water
It is very similar to sodium’s reaction but it’s slower because it’s melting point is higher so heat isn’t produced so quickly and it doesn’t melt
All these metals react with water to produce _______ ____________ which are acidic or alkaline?
Metal hydroxides
Alkaline
What happens when potassium reacts with water
Faster than sodium’s. Enough heat is given off to ignite the hydrogen which burns with a lilac flame
How do rubidium and caesium react with water
Even more violently than potassium and can be explosive
What is the reason for the increase in reactivity as you go down the group
All alkali metals have one electron in the outer shell. As you go down, the outermost electron is in a shell which is further from the nucleus therefore the attraction between the electron and nucleus becomes less. As you go down group 1 the atoms get bigger and the outer electron is more easily lost
All group 1 metal ions are colourless which means that their compounds will be colourless or ________ if they are combined with a coloured negative ion
White
The hydroxide formed is an _____
Ion
True or false: All group 1 elements are non-metals
False. They are all metals
True or false: All group 1 elements are soft with melting points and densities which are very low for metals
True
True or false: All group 1 elements have to be stored out of contact with air or water
True.
True or false: All group 1 elements react rapidly with air to form coatings of metal oxide
True
True or false: all group 1 elements react with water to produce an acidic solution of the metal hydroxide and hydrogen gas
False. All group 1 elements react with water to produce an ALKALINE solution of the metal hydroxide and hydrogen gas
True or false: all group 1 elements decrease in reactivity as you go down the group
False. All group 1 elements increase in reactivity as you go down the group
True or false: all group 1 elements form compounds in which the metal has a 1+ ion
True
If you followed trends in group 1 then you could predict what about francium:
- Francium is very soft with a melting point just above room temperature
- Would react violently with water to give francium hydroxide and hydrogen
- Francium hydroxide solution will be strongly alkaline
- Francium compounds are white and dissolve in water to give colourless solutions
As you go _________ group 1, the outermost electron is in a shell that’s further from the nucleus. Which means that the _____________ between the outermost electron and the nucleus becomes less. The atoms lose electrons more easily and the atoms get ___________ - therefore the metals are ________ reactive.
Down
Attraction
Bigger
More
What state is a hydroxide in
Aqueous
When alkali metals react with water, each property has a different _________ _________
State symbol
