Alkali Metals2

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Alkali Metals



The alkali metals are a group of chemical

elements in the periodic table with verysimilar properties: they are all shiny, soft,

silvery, highly reactive metals at standard

temperature and pressure and readily lose

their outermost electron toform cations with charge.



• Lower densities than other metals

• One loosely bound valence electron

•

Largest atomic radii in their periods• Low ionization energies

• Low electronegativities

•

Highly reactive



The alkali metals generally become more dense down

the group.

Element Density (g/cm3)

LithiumSodium

Potassium

Rubidium

Caesium 1.87

1.53

0.86

0.970.53



All alkali metals have 1 electron in their outer shell.

sodium2,8,1

lithium2,1

potassium

2,8,8,1



The reactivity of alkali metals increases

down the group.

Cs

Rb

K

Na

Li

The size of each element’s

atoms, and the number of

full electron shells,

increases down the group.

i n c

r e a s e

i n r

e a

c t i v i t y



The melting point of alkali metals decreases

down the group.

Element Melting point (°C)

Lithium

Potassium

Sodium

Rubidium

Caesium

181

98

64

39

28



When alkali metals are heated and added to a jar of

oxygen, they burn fiercely with a coloured flame.

lithium

burns with a red

flame

sodium

burns with an

orange flame

potassium

burns with a

lilac flame



• is a soft, silver-white metal that belongs to

the alkali metal group of chemical elements.

• Lithium and its compounds have several

industrial applications, including heat-resistant

glass and ceramics, high strength-to-

weight alloys used in aircraft, lithium

batteries and lithium-ion batteries.



• Compounds Available:

Lithium Acetate (LiCH3COO)

Synonym: Acetic Acid Lithium Salt

Use: buffer for gel electrophoresis of DNA and RNA

Lithium Oxide (Li2O)

Synonym: Lithium Monoxide, Lithia

Use: flux for ceramic glazes



Lithium Nitrate (LiNO3 )

Use: manufacture of red colored fireworks and flares

Lithium Aluminate (LiAlO2)

Synonym: lithium aluminium oxide, Lithium

alumanoylolate

Use: inert electrolyte support material of molten

carbonate fuel cells

Lithium Perchlorate (LiClO4 )

Synonym: Perchloric acid, lithium salt

Use: source of oxygen in chemical oxygen generators



• Pharmaceutical Preparations:

Lithium Citrate (Li3C6H5O7)

Litarex – is an international brand name for lithium citrate used to treat and preventepisodes of mania in people with bipolar disorder (manic depressive disorder).



Lithium Carbonate ( Li2CO3 )

Eskalith is commonly prescribed to treat bipolar disorder (also known as manic depression).



• It is a soft, silvery-white, highly reactive metal and is

a member of the alkali metals; its only

stable isotope is Na.

• Various industries including petroleum, chemicals,

soaps, textiles and paper have found sodium

compounds extremely beneficial for their processes.



•Compounds Available:

Sodium Bicarbonate (NaHCO3 )

Synonym: baking soda, bread soda, cooking soda, and bicarbonate of soda

Use: relieves sour stomach

Sodium Peroxide (Na2O2 )Synonym: Sodium dioxide, Flocool, Solozone,Disodium

peroxide

Use: used to bleach wood pulp for the production of paper

and textiles

Sodium Chlorate (NaClO3 )

Synonym: Sodium chlorate(V)

Use: used for making ClO2



Sodium Thiosulfate (Na2S2O3)

Synonym: Sodium hyposulfite, Hyposulphite of soda

Use: used in components of hand warmers andother chemical heating pads

Sodium Silicate (Na2SiO3 )Synonym: Liquid glass, Waterglass

Use: used in cements, passive fire protection,refractories, textile and lumber processing andautomobile



• Pharmaceutical Preparations:

Sodium Sulfate (Na2SO4 ) is also known as Glauber’s Salt,

Thenardite

Moviprep - is an osmotic laxative indicated for cleansing of

the colon as a preparation for colonoscopy in adults 18

years or older.



Sodium Valproate ( C8H15 NaO2 )

Epilim - medicine that is used mainly to

treat epilepsy.



• is a soft silvery-white alkali metal that oxidizes rapidlyin air and is very reactive with water, generating sufficientheat to ignite the hydrogen emitted in the reaction.

Uses:

• fertilizers – potassium is an essential element for plants. It is usually added as a chloride, sulfate ,nitrate or carbonate.

• fireworks and explosives – as potassium nitrate and potassium chlorate.

• food preservation – as potassium nitrate.



•Compounds Available:

Potassium Chlorate (KClO3)

Synonym: PotcrateUse: used as an oxidizing agent, disinfectant, explosives

and fireworks

Potassium Sulfate (K 2SO4)Synonym: Potassium sulphate

Use: used as fertilizers

Potassium Hydroxide (KOH)Synonym: caustic potash

Use: manufacture of biodiesel and soaps, petroleum

refineries



Potassium Carbonate (K 2CO3)

Synonym: Potash, pearl ash

Use: used in the production of soap and glass

Potassium Nitrate (KNO3 )Synonym: Salt petre, Nitrate of potash, Vesta

powder

Use: used as fertilizers, food additive, rocket propellant and fireworks



Pharmaceutical Preparations:

Potassium Chloride (KCl) is alsoknown as Klorvess

Aldactone – used to treat patients

with hypokalemia.

Potassium Iodide (KI) is also known

as Iodide of Potash

Yodefan – used to treat lung

conditions or disease in which mucus

complicates the condition.



Potassium Citrate (C6H5K 3O7 ) is also known as Kaliksir,

Urocit-K - used to make the urine less acidic.



• is highly reactive, with properties similar to those of other

elements in Group 1, such as very rapid oxidation in air.

•it is used in infrared radiation producing pyrotechniccompositions as a colorant and an oxidizer

in decoys and illumination flares. It is also used as a raw

material for preparation of other rubidium compounds

and rubidium metal, for manufacture of catalysts andin scintillation counters. It finds uncommon use

in fireworks to produce a red-violet color.




• Rubidium Carbonate (Rb2CO3 )

Use: used in glass making

• Rubidium Hydroxide (RbOH)

Use: used in scientific research

• Rubidium Iodide (RbI)

Use: used in infrared radiation producing pyrotechnic

compositions as colorant and oxidizer

• Rubidium Nitrate (RbNO3 )

Use: compound with a melting point of 642 °C



• Pharmaceutical Preparation:

• Rubidium Chloride (RbCl)Use: depressant



• It is a soft, silvery-gold alkali metal with a melting

point of 28 °C (82 °F), which makes it one of only

five elemental metals that are liquid at (or near) room

temperature.

• Caesium is used in atomic clocks, removing air traces

from vacuum tubes, and in ion propulsion systems.




•Cesium Iodide (CsI)Use: used as an input phosphor of an xray image intensifier

tube

• Cesium Chloride (CsCl)

Use: used in isopycnic centrifugation

•

Caesium bromide (CsBr)Use: used in optics as a beamsplitter component in wide

band spectrophotometer



• Caesium hydroxide (CsOH)

Use: used as a powerful base

• Caesium nitrate (CsNO3)

Use: same with Rb NO3



• It was formerly known as eka-caesium and

actinium K. It is one of the two

least electronegative elements, the other

being caesium.



Chapter Quiz



•

What is the family name for the Group 1 or1A elements?

A: alkaline earth metalsB: transition metals

C: alkali metals

D: halogens



• Alkali metals have how many valence electrons?

A: 4

B: 3

C: 2

D: 1



•

Because of the one valence electron, alkalimetals are __________________ reactive.

A: notB: highly

C: somewhat



• Which of the alkali metals is the most

reactive?

A: lithiumB: potassium

C: francium

D: cesium



• Lithium is used in each of the following waysexcept...

A: batteries

B: medications for bipolar disorder

C: airplane parts

D: all of the above



• 6. Also known as baking soda?

• 7. What is the international brand name for

lithium citrate?

• 8. What is the synonym name of NaSO4?

• 9. Give 1 property of Alkali Metals.

•

10. Ehat is the flame color of Potassium?

Alkali Metals2

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