Chemistry, asked by Nazeer987, 3 months ago

How aluminium is used in flashlight photography?​

Answers

Answered by debanjanadey59
0

Answer:

thanks for free points bye

Answered by Kathonkoner
0

Answer:

your answer.pls follow me and I also follow u

Explanation:

ALUMINIUM FLASHLIGHT Aluminium bronze powder, also known as " silver bronze," may be used in place of, or in conjunction with, magnesium for flashlight work. It is cheaper than magnesium, burns under cer tain conditions with less smoke, but it is not quite so actinic. The first experiments with this metal appear to have been carried out by Dr. Piffard, of New York, in i888. Dr. Miethe has found that fine aluminium bronze powder (5 to io per cent. of aluminium and 90 to 95 per cent. of copper) burns almost completely in the flame of a Bunsen burner. Aluminium, how ever, is better, even if more dangerous, when mixed with potassium chlorate, in which form it becomes an explosive mixture, and must be treated as such ; that is to say, the mixture must have a light applied to it, and not be blown through a flame. The potassium chlorate intended for mixing with the aluminium bronze powder should be quite free from the deliques cent potassium chloride, because if this is present the chlorate will tend to be moist. The chlorate should be well dried, and powdered sufficiently finely as to pass through a sieve of eighty meshes to the inch. The aluminium and the chlorate must not be mixed together in a mortar, but with a feather or a flat blade on a sheet of paper. A suitable formula is : Aluminium . . . i part.

Potassium chlorate . 2 parts.

For more rapid flashes, antimony sulphide should be added, the formula being : Antimony sulphide . . 3 parts.

Aluminium . • • 5 ,1 Potassium chlorate . . 15 „ Another formula is : Aluminium . . . 20 parts.

Lycopodium . . . 5 11 Ammonia nitrate . . I part.

All these mixtures are explosive and dangerous, and proper precautions should be observed, as directed under the heading " Flashlight Mixtures," where a formula for aluminium in conjunction with magnesium will be found.

A flashlight mixture, patented in 1904 by Dr. G. Krebs, gives very little smoke and consists of aluminium 2 parts, 2 parts, and chrome alum Do parts. A " time " powder, also due to Dr. Krebs, contains aluminium 20 parts, magnesium 80 parts, chrome alum or copper sulphate loo parts, lime oxide, carbonate, or glass 20 parts. Aluminium cartridges, to con tain a flash mixture and burn with it, have lately been made, the metal case being of from •1 to •3 mm. thickness.

Aluminiun leaf burned in oxygen gives a very powerful light. The method is to place a few leaves of aluminium in a dry bottle containing oxygen gas, and on applying a lighted taper to the top leaf the contents of the bottle burn with a flash which, for actinic power and general brightness, is said to exceed anything obtainable with an equal amount of magnesium.

Similar questions