Gold, Physics

Gold:                        

Atomic number

79

Symbol

Au

Atomic weight

196.9665

discovery

Known since prehistoric time

Electrical configuration

[Xe]6s'4f145d10

Word origin

Sanskrit, jwal: meaning gold also Latin aurum, shining drawn.

Melting point

1064.430C

Boiling point

27000C

Specific gravity

18.88 (200C)

Electrical resistivity

2.2*10-8 ohm-m

Properties:

1.      In mass, gold is a yellow coloured metal, although it may be black, ruby, or purple when finally divided.

2.      It is one of the stable metals and it is very light and soft.

3.      It is a malleable and ductile and can be easily beaten into translucent sheets as thin as 0.00001mm.

4.      It is a good conductor of electricity and heat. It is not affected by exposure to air or to most reagents.

5.      It is inert and good reflector to infrared radiation.

6.      It is very soft and cannot be used in pure form. So, it is usually alloyed to improve its resistance to mechanical wear and to impact hardness.

7.      It is highly corrosion resistant which makes it alloy very much useful as contact materials in electric field.

Uses:

1.      Gold is used in coinage and is the standard for many monetary systems.

2.      It is used for jewellery, dental work, plating and reflectors.

3.      Chlorauric acid is used in photography for toning silver images.

4.      Disodium aurothiomalate administered intramuscularly is a treatment for arthritis.ents

5.      It is extensively used to make contacts on very sensitive devices where clean contact surface is essential. It is also used in inter connections within the integrated circuits.

Sources: Gold is generally found in veins among rocks and ores of other metal. It is also found in the form of dust in the beds of rivers. Gold is widely distributed and almost always associated with pyrite or quartz.

Posted Date: 7/21/2012 7:46:23 AM | Location : United States







Related Discussions:- Gold, Assignment Help, Ask Question on Gold, Get Answer, Expert's Help, Gold Discussions

Write discussion on Gold
Your posts are moderated
Related Questions
Bronze: Copper when alloyed with tin (8% to 16%) and a very small percentage of a third element like cadmium, beryllium, phosphorous, silicon etc, is called Bronze. Bronzes are gi

An electron is constrained to the central perpendicular axis of a ring of charge of radius 2.2 m and charge 0.015 mC. See Section 22-6. Suppose the electron is released from rest a

what is an atom

Explain Ballast Volume Pressure? Two containers I and II prodigal with an ideal gas are connected by two small openings of the same area, A, through a ballast volume B. The tem

Ultra violet Waves: The wavelength of ultra violet wave from 380mm down to 60nm.


Q. Is air travel time the similar whether or not the plane is flying with or against the rotation of the Earth? Answer:- All air travel gets the earth's rotation into acco

anyone guide me about the explanation of coulombs law

When is a system said to have attained equilibrium. Illustrate. The change in entropy of a system, in a procedure is positive. Would the process be a spontaneous one? Describe.

The vapour pressure of a substance at  20.0 o C is 38.1  kPa and its enthalpy of vaporisation is 49.6  kJ mol -1 . Estimate the temperature at which its vapour pressure is 80.0 k