Aluminium, Physics

Assignment Help:

Aluminium

 

Atomic number

13

Symbol

Al

Atomic weight

26.98154

Discovery

Wohler 1827

Electronic configuration

[Ne] 3p'

Word origin

Latin alumen: alum, an astringent and dyeing mordant.

Melting point

660.370C

Atomic number

24670C

Symbol

2.6989

Electrical resistivity

2.8*10-8 ohm-m

Properties:

1.      Pure aluminium is a silvery-white metal.

2.      It is a soft, light, relatively non toxic, with a high thermal conductivity.

3.      It can be easily formed, machined, or cast.

4.      It is second among metals in terms of malleability and sixth in ductility. It can be put to a shape as per need by rolling, drawing, spinning and forging.

5.      Like copper, aluminium also forms an oxide layer over its surface when exposed to atmosphere and that layer prevents the materials from further oxidation and acts as a insulation because aluminium oxide has relatively higher resistivity. Thus, the contact resistance of aluminium wires is very high.

6.      It can be suitably alloyed with variety of other elements to cause an increase in strength and hardness.

7.      Aluminium coatings are highly reflective to both visible and radiant heat. The coatings form a thin layer of protecting oxide and do not deteriorate like silver coatings.

8.      It is nonmagnetic and nonspeaking.

Uses:

1.      Ancient Greeks and Romans used alum as and astringent for medical purposes and as a mordant in dyeing.

2.      It is used in kitchen utensils & exterior decorations.

3.      It is widely used as conductor for power transmission and distribution.

4.      It is also used in overhead transmission lines, bus bars, ASCR conductors etc.

5.      The alloys of aluminium are used in construction of aircraft and rockets.

6.      Reflective aluminium coatings are used for telescope mirrors, making decorative paper & packaging.

7.      Aluminium is used in glass making and refractories.

Sources: Aluminium is the most abundant metal in the earth crust (8.1%), although if it is not found free in nature. Cryolite is an aluminium ore, although it has been replaced for commercial aluminium purification by an artificial mixture of sodium, aluminium and cadmium fluorides. The Bayer process is commonly used to refine the impure hydrated oxide ore, bauxite, for use in the Hall-Heroult refining process. Aluminium also can be produced from clay, although this is not the most economically feasible method at present. In addition to Cryolite and bauxite, aluminium is found in feldspars, granite, and many other common minerals. Two oxide, alumina, occurs naturally as ruby. Sapphire, emery and corundum.


Related Discussions:- Aluminium

Light, diffenrence between pure and impure spectrum.

diffenrence between pure and impure spectrum.

Define wave, A wave is a disturbance which transmits power and momentum fro...

A wave is a disturbance which transmits power and momentum from one place to the other without the transport of matter.

Second law of motion, A 25 N box is pulled vertically upward by means of a ...

A 25 N box is pulled vertically upward by means of a cord.Find the acceleration of the box if the tension in the cord is 35 N.

Evaluate the change in entropy, Two 1100-kg cars are travelling 95 km/h in ...

Two 1100-kg cars are travelling 95 km/h in opposite directions when they collide and are brought to rest. Estimate the change in entropy of the universe as a result of this collisi

Heat therapy, Normal 0 false false false EN-US X-NONE...

Normal 0 false false false EN-US X-NONE X-NONE

Draw the circuit diagram of a common-emitter amplifier, Draw the circuit di...

Draw the circuit diagram of a common-emitter amplifier using an n-p-n transistor, Draw the Input and 1p waveforms of the signal. Write the expression for its voltage gain

Explain antinodes of standing waves, The points of maximum amplitude are ca...

The points of maximum amplitude are called as antinodes. At ends density and air pressure both are very low.

Definitions of effect modifying variables, Clear definitions of, and ration...

Clear definitions of, and rationale for defining variables as explanatory confounding (if required) effect modifying variables (if required) and rationale if the form

Estimate the temperature of vapour pressure, The vapour pressure of a subst...

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

Why is quantum mechanics important, Why is quantum mechanics important? ...

Why is quantum mechanics important? Quantum mechanics is important to understand the behavior of systems at atomic length scales and duration smaller. For illustration, when Ne

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd