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Alkali Metals

Elements found in Group 1 (found on the left-hand side of the periodic table) are referred to as the alkali metals. Their outer shell has 1 electron in it, which is usually given away in chemical reactions.

Lithium (Li)

Lithium (Li)

  • Lithium has the electron structure (2,1).
  • Lithium is the least reactive of the alkali metals.
  • Lithium burns with a crimson flame when it reacts with oxygen.
  • Lithium floats on the surface of water and will release bubbles of hydrogen gas (it effervesces).
Sodium (Na)

Sodium (Na)

  • Sodium has the electron structure (2,8,1).
  • Sodium is more reactive than lithium because its outer electron is less strongly attracted to the positively charged nucleus. This is because it is a greater distance from the positive charge of the atom's nucleus.
    • Sodium also has a lower melting point than lithium.
    • Sodium is denser than lithium.
  • The metal floats on the surface of water, which releases enough heat to melt the sodium. The sodium moves quickly across the surface of the water.
  • Sodium burns with a yellow/orange flame when it reacts with oxygen.
Potassium (K)

Potassium (K)

  • Potassium has the electron structure (2,8,8,1).
  • It's more reactive than lithium and sodium because its outer electron is least strongly attracted to the nucleus.
    • Potassium also has a lower melting point than sodium.
    • Potassium is denser than sodium.
  • The metal floats on the surface and then it burns with a lilac flame when it reacts with oxygen.
Jump to other topics
1

States of Matter

2

Atoms, Elements & Compounds

3

Stoichometry

4

Electrochemistry

5

Chemical Energetics

6

Chemical Reactions

7

Acids, Bases & Salts

8

The Periodic Table

9

Metals

10

Chemistry of the Environment

11

Organic Chemistry

11.1

Formulae, Functional Groups & Terminology

11.2

Naming Organic Compounds

11.3

Fuels

11.4

Alkanes

11.5

Alkenes

11.6

Alcohols

11.7

Carboxylic Acids

11.8

Polymers

12

Experimental Techniques & Chemical Analysis

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