Alkali Metals Flashcards
Where can Alkali metals be found in the PT?
The element of group one are known as alkali metals.
E.g - Lithium, Sodium and Potassium.
What are some properties of Alkali Metals? (3)
- They are very reactive, as they only have one electron in their outer shell.
- They are SOFT metals with LOW DENSITIES.
- They are so reactive that they react instantly with oxygen and are found naturally in compounds like metal oxide. Pure alkali metals must be stored in oils to prevent this.
Reaction with water?
Alkali Metal + Water === Metal Hydroxide + Hydrogen
How does reactivity increase down Group 1?
- As atoms get bigger they have more electron shells.
- The outer electron is further away from the nucleus.
- The attraction between the outer electrons and the
nucleus becomes weaker. - This makes it easier for an atom to lose its outer electron.
Melting and boiling points in the group?
They decrease down the group.
What are Ionic Compounds?
Alkali metals oonly have one electron in their outer shell, so they are very keen to lose it to form a 1+ ION. They are so keen that they only react to form ionic compounds.
Where does the name ‘Alkali Metals’ come from?
The hydroxides that are formed when alkali metals react with water will dissolve to make alkaline solutions.
What happens when they react with chlorine?
The alkali metals react vigorously when heated in chlorine gas to form white metal chloride solid salt. You would also see yellow chlorine gas and a bright flame.
(Alkali metal + Chlorine = Metal chloride)
What are products of reactions between metals and non metals?
The product tends so be white solids which dissolve to form a colourless solution.
Reaction with Oxygen?
Produces a metal oxide. Produces a layer of oxide on the metal, called tarnish.
What happens when lithium reacts with water?
Forms lithium hydroxide and hydrogen.
You can see it fizzing, move across the surface then dissolve
What happens when sodium react with water?
Forms sodium peroxide and hydrogen.
You can see it fizzing, move across the surface and dissolve.
What happens when potassium reacts with water?
Form potassium hydroxide and hydrogen.
You can see it fizziing, move across the surface, dissolve and a lilac flame.
