iNorganic chemistry assigment

The color of gold ....

Gold is element which in periodic table has a symbol Au (Aurum) and the atomic number is 79. Gold also is a metallic element who has a color. The color of gold is called golden yellow. Golden yellow is the color half way between amber and yellow. It is color that is 87,5% yellow and 12,5% red. The first recorded use of golden yellow as a color name in English was in the years 1597. Amber is an orange- yellow color that got its name from the material known as amber. Due to this, amber can refer not to one but to series of shade of orange (shown below in the shades of amber color comparison chart), since the natural material varies from nearly yellow when newer to orange or reddish-orange when older.

The golden colloid also has a high color, the color is purple. The color of gold is caused by gold plasmon frequency (frekuensi plasmon emas) is located on julat sight (julat penglihatan). That cause the red and yellow color will be reflected, meanwhile the blue color will be absorbed. Just the silver colloid has same interaction with shine, but on the shorter frequency, so cause the silver colloid will be yellow color.

The color of copper ...

Copper has a reddish, orangish, or brownish color because a thin layer of tarnish (including oxides) gradually forms on its surface when gases (especially oxygen) in the air react with it. But pure copper, when fresh, is actually a pinkish or peachy metal. Copper and gold are the only two elemental metals with a natural color other than gray or silver. The usual gray color of metals depends on their "electron sea" that is capable of absorbing and re-emitting photons over a wide range of frequencies. Copper has its characteristic color because of its band structure. In its liquefied state, a pure copper surface without ambient light appears somewhat greenish, a characteristic shared with gold. When liquid copper is in bright ambient light, it retains some of its pinkish luster. When copper is burnt in oxygen it gives off a black oxide.