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

Compute the voltage gain with feedback, Q. The voltage increase of an ampli...

Q. The voltage increase of an amplifier without feedback is 100. If negative feedback is functioned with feedback fraction 0.1, compute the voltage gain with feedback. A F

Explain irreversible process, Explain irreversible process A process wh...

Explain irreversible process A process which takes the system to the non equilibrium state is known as irreversible process.  *It can't be retraced in the reverse direction.

Positive charge on n-side of the junction, Positive charge on n-side of the...

Positive charge on n-side of the junction Some  of  the  free  electrons  move  across  the junction  from  n-type  to  p-type, leaving  behind  positive  donor  ions  as  they

Determine potential difference between two points, If 10 joules of energy a...

If 10 joules of energy are required to move 5 coulombs of charge between two points, the potential difference between the two points is equal to how many volts? Ans: If 10 j

Electric potential of a solid object, Which statement concerning the electr...

Which statement concerning the electric potential of a solid object made out of a perfectly conducting medium is most correct? Answer: It is the electric field which is ze

Examine application of thin film technology, 1) Examine a particular thin f...

1) Examine a particular thin film system in some depth -review the literature. Ag deposited on GaAs Al deposited on Si Fe/Cr/Fe multilayer structures   2) E

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

Nuclear medicine image reconstruction, Consider the projection data shown i...

Consider the projection data shown in Figure 1. Starting with 0 activity in each pixel and using the algebraic reconstruction technique, determine the activity in the 9 image pixel

Explain spring force (fspring), Explain Spring Force (Fspring) Force ex...

Explain Spring Force (Fspring) Force exerted by a compressed or stretched spring upon any object that attached to it. An object that compresses or stretches a spring is always

How is a galvanometer converted into an ammeter, Q. How is a galvanometer c...

Q. How is a galvanometer converted into (a) an ammeter and (b) a voltmeter? A galvanometer is transformed into an ammeter by connecting a low resistance in parallel with it. Th

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