Group #1 Alkali Metals

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Group #1 Alkali Metals
By: Gene, Tori, Sammi, Tom
Origin of the group
★ The word alkali comes from the Arabic word for ashes.
★ Alkali is now used as another word for base.
★ Alkali metals react with water.
General Characteristics of group
★ All of the elements are solids at room temperature
except Caesium.
★ All of the elements have a silverish tint to them except
Caesium which is a metallic gold.
★ The melting points decrease as you go down the group.
★ These elements have low densities compared to other
elements.
Lithium (Li)
★ Element: Lithium
★ What: 1st element in group one.
★ Density: 0.534 g/cm3
★ Phase at Room Temperature: Solid
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Melting Point: 180.5 degrees celsius
Characteristics: Silvery, lightest of all metals, moist air causes corrosion.
Origin of Name: Lithium derived from ‘lithos’, the Greek word for stone.
Who/When: 1817 by Johan August Arfwedson
Use of Element: Lithium is used for mental illnesses, for eating disorders, and for
blood disorders.
Sodium (Na)
★ Element: Sodium
★ What: 2nd element in group one.
★ Density: 0.97 g/cm3
★ Phase at Room Temperature: Solid
★ Melting Point: 97.794 degrees celsius
★ Characteristics: Silvery-White so soft a room temperature you can cut it with a
butter knife
★ Origin of Name: from the English word "soda" the origin of symbol Na from the Latin word
"natrium"
★ Who/When: Sir Humphry Davy discovered in England in 1807
★ Use of Element: Sodium is used as a coolant in nuclear reactors, and as a reactant in
organic chemistry
Potassium (K)
★ Element: Potassium
★ What: 3rd element in group one.
★ Density: 0.89 g/cm3
★ Phase at Room Temperature: Solid
★ Melting Point: 63.5 degrees celsius
★ Characteristics: Silvery- White and lustrous
Origin of Name: from the English word "potash", the Arabic word "qali" meaning alkali, the
origin the symbol K comes from the Latin word "kalium".
★ Who/When: Potassium metal was first isolated by Sir Humphery Davy in 1807
★ Use of Element: Potassium is used in organic chemistry as a powerful Reducing Agent
Rubidium (Rb)
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Element: Rubidium
What: 4th element from the top in group one.
Density: 1.53 grams per centimeter cubed
Phase at Room Temperature: Liquid
Melting Point: 39.48°C
Characteristics: Silvery-white, metallic
Origin of Name: From the Latin word "rubidius" meaning "dark red" or "deepest red".
Who/When: 1861 by Robert Bunsen & Gustav Kirchoff. Found in the mineral lepidolite by using
a spectroscope.
★ Use of Element: It has been used as a component of photocells, andit is sometimes used in
fireworks to give them a purple color.
Caesium (Cs)
★ Element: Caesium
★ What: 6th element in group one.
★ Density: 1.873 g/cm3
★ Phase at Room Temperature: Solid
★ Melting Point: 28.44 degrees celsius
★ Characteristics: soft, gold-coloured metal
★ Origin of Name: from the Latin word "caesius" meaning "sky blue" or "heavenly blue".
★ Who/When: Discovered by Gustav Kirchhoff and Robert Bunsen in 1860
★ Use of Element: Used as a drilling fluid, to make special optical glass, as a catalyst promoter, in
vacuum tubes and in radiation monitoring equipment.
Francium (Fr)
★ Who: Marguerite Perey discovered Francium in 1939
★ What: Last alkali metal, atomic number 87 and atomic weight of 223 amu,
it occurs naturally and is a solid at room temperature.
★ Where: Curie Institute in Paris, France
★ How: francium-223 is made naturally when actinium-227 emits an alphaparticle
★ Melting Point: 27oC (300 K) (Pretty low)
★ Density: 1.873 g/cm3
Francium (Fr)
Characteristics: Francium is a heavy, unstable, radioactive metal with a
maximum half-life of only 22 minutes.
Fun Facts:
● Francium is the second rarest element in the Earth’s crust, next to astatine.
Less than thirty grams of francium exists on Earth at any given time.
● The discovery of francium completed humankind’s discoveries of naturally
occurring elements.
● Francium, like the other alkali metals, reacts in the present of water.
Uses of Francium: Commercially, there are no uses for francium, due to its
rarity and instability. It is used for research purposes only.
Reactivity of Alkali Metals
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