Understanding Alkali Metals: Properties, Reactions, and Applications

This is an educational document that provides an in-depth exploration of the alkali metals, specifically referred to as the lithium family. The presentation covers various characteristics, electronic configurations, and chemical properties of alkali metals such as lithium, sodium, potassium, rubidium, and cesium. These metals are described as highly reactive, electropositive, and excellent conductors of heat and electricity, typically forming +1 cations. The document details how these metals interact with elements like hydrogen and oxygen and their reactions with water to release hydrogen gas.

Additionally, the presentation explains the extraction of sodium through Down's electrolytic process, highlighting the conditions and chemical reactions involved in producing sodium and chlorine gas from sodium chloride. This document is particularly useful for students or researchers interested in the fundamental properties of alkali metals and their applications in various chemical processes. The presentation concludes with a section inviting queries, indicating it's designed for an educational setting, likely a lecture or classroom discussion.

1. ALKALI
A Lithium Family
METAL

3. Is a gas at room temperature and
has a very low boiling and melting
point.
Doesn't react with water vigorously
to produce alkaline solutions.
Can either form a cation with a
charge of +1 or an anion with a
charge of -1.
Unique properties distinguish it
from both metals and nonmetals.

4. Very reactive and not found in free
states.
Highly malleable and ductile.
Highly electropositive metals.
Sharp edges can be used to cut soft
metals.
Monovalent and have oxidation
number +1.
Low specific gravity.
CHARACTERS
Electronic Configuration: ns
1

5. Posses silvery-white metallic lustre
while freshly cut.
Have low melting and boiling points
due to weak metallic bonds.
Li Crimson
Na Golden Yellow
K Pale violet
Rb Reddish violet
Cs Blue violet
CHARACTERS
Why do alkali metals make such good friends?

6. Possesses low ionization energy on
going down the group.
Have low values of electro-
negativities.
Good conductors of heat and
electricity.
CHARACTERS
Why did the alkali metal get a job at the bank?

8. Highly electropositive and reduce H to form metal
hydride.
CHEMICAL PROPERTIES
2
2K + H 2KH
2
Reacts with water to liberate hydrogen gas.
2Na + H O Na O + H
2 2 2
Nitrate of Alkali forms O gas on heating.
2KNO O + 2KNO
2
23
∆

9. Form alkali with oxygen (Metal Oxides /
Hydroxides)
CHEMICAL PROPERTIES
4Na + O 2Na O
2
Forms water-soluble carbonate, sulphate and
phosphate with acid.
2Na + H CO Na CO + H
2
2
Na O + H O 2NaOH
2 2
332 2
2Na + H SO Na SO + H
6Na + 2H PO 2Na PO + 3H
2 4 2 4 2
2433 4

10. DOWN'S
ELECTROLYTIC
PROCESS
Extraction of Sodium
Are very strong reducing agent,
their oxides and halides cannot be
reduced by other elements or
compounds chemically.
Halides of alkali metals cannot be
easily roasted to obtain their oxides.
A high range of temperature is
required for the reduction of halide
or oxides of alkali metals

11. When electricity is passed through fused
sodium chloride having graphite as an
anode and iron ring as a cathode.
The following reaction is observed:
2NaCl 2Na + 2Cl
2Cl Cl + 2e (Oxidation)
2Na + 2e 2Na (Reduction)
PRINCIPLE
At anode:
At cathode:
2

12. NaCl and CaCl2 are mixed in the ratio of 2:3 and
melted in down’s cell at around 600°C
When electricity is passed through the fused
electrolyte, NaCl ionizes into Na and Cl
Na being a positive charge is attracted towards the
cathode and gains electron and become a neutral sodium
atom, which collects in the iron receiver as globules
Cl is attracted towards cathode and loses electron,
becomes a neutral Cl atom, which combines with another
Cl atom and comes out through a wire gauze dome as Cl2
Obtain both sodium metal as well as chlorine gas

15. QUERIES TIME

16. THANK YOU