Group 1 Elements and Alkali Metals

Practice flashcards covering the physical properties, chemical reactions, extraction methods, and specific terminology associated with Group 1 alkali metals.

Group 1 Elements

Elements characterized by having one loosely bound valence electron in their outermost shell, very low electronegativity, and the formation of univalent, colorless compounds.

Spodumene

A silicate mineral with the formula $LiAl(SiO_3)_2$ used as a source for obtaining Lithium.

Lepidolite

A silicate mineral source for Lithium with the chemical formula $KLi_2Al_2(SiO_3)_3(FOH)_2$.

Rock Salt

The largest source of Sodium, chemically known as $NaCl$.

Sylvite

A mineral deposit occurring as $KCl$, used as a source for Potassium.

Carnalite

A double salt source for Potassium with the formula $KCl \times MgCl_2 \times 6H_2O$.

Francium

A radioactive alkali metal with a short half-life of $21\,\text{minutes}$, formed from the alpha decay of actinium.

Downs Cell

The apparatus used for the production of sodium via the electrolysis of a molten mixture of $NaCl$ and $CaCl_2$.

Cohesive Energy

The force holding atoms together in a metal; its magnitude determines the hardness and melting/boiling points of the element.

Photoelectrons

Electrons emitted from an atom when it absorbs light energy; this phenomenon explains the use of Cesium and Potassium in photoelectric cells.

Flame Colors

Characteristic colors emitted by alkali metals when heated: Lithium (Crimson), Sodium (Yellow), Potassium (Lilac), Rubidium (Red), and Cesium (Blue).

Saline Hydrides

White crystalline solids with an $NaCl$ crystal structure formed when Group 1 metals react with hydrogen; example includes $LiH$.

Lithium Aluminium Hydride ($LiAlH_4$)

A complex hydride formed by Lithium that serves as a useful reducing agent.

Normal Oxides (Monoxides)

Oxides containing the $O^{2-}$ ion where the oxidation state of oxygen is $-2$; formed primarily by Lithium ($Li_2O$).

Peroxides

Compounds containing the $O_2^{2-}$ ion (oxygen oxidation state $-1$), such as $Na_2O_2$, which is used for bleaching wood pulp and fabrics.

Superoxides

Compounds containing the $[O_2]^-$ ion (oxygen oxidation state $-1/2$), such as $KO_2$, used in life support systems like space capsules to produce oxygen and remove $CO_2$.

Lithium Nitride ($Li_3N$)

The compound formed when Lithium, the only Group 1 element to do so, reacts with dinitrogen ($N_2$).

Oxosalts

Salts containing oxygen as an anion, including carbonates, bicarbonates, nitrates, and nitrites, which are particularly stable in Group 1 due to high electropositivity.

Diagonal Relationship

A chemical similarity between elements in the second period and their diagonal neighbors in the third period (e.g., $Li$ and $Mg$) due to similar effects of size, charge, and electronegativity.

Deliquescent

The property of being able to absorb moisture from the air and dissolve in it; applicable to the nitrates of Lithium ($LiNO_3$) and Sodium ($NaNO_3$).

Disproportionate

A chemical reaction where a substance is simultaneously oxidized and reduced, as seen with nitrites when heated in the absence of air.

Sodium Thiosulphate ($Na_2S_2O_3$)

Produced by reacting $Na_2SO_3$ with powder sulphur, this compound is useful in photography and iodine titrations.