Compose the words from A and C which are the metals to get thword in B which is an alloy. Comment what properties do these alloys possess

The Protection of Steel Work by Zinc

Zinc _1_ are one of the best methods for the protection of steelwork against _2_. There are two reasons for this, the first being that zinc is itself _3_ to normal atmospheric corrosion. In most atmospheric conditions the rate of attack on zinc is only 3-10 per cent that on steel, and this is due to _4_ the grey impermeable film which forms over the surface of the metal exposed to air. This _5_ further attack, although in industrial atmospheres containing sulphur dioxide the film is _6_ stable because it consists _7_ of basic zinc carbonate which reacts with the sulphurous acid. Thus, a coating of metallic zinc on steelwork forms a _8_bar­rier affording considerable _9_ under normal conditions. The second reason _10_ from the fact that zinc is considerably _11_ electronegative than iron, and when the two metals are in contact in an electrolyte, zinc tends to dissolve, leaving the iron _12_.

coat corrosive resist main resist little large during protect arise much attacked

Model: copper brass zink

Commentary: The main constituents of brass are copper and zink. Due to zink it has an excelent corrosion resistance.

A	B	C
1 carbon (apr. 2%)	Bronze	a. aluminium
2. copper	Steel	b. iron
3 iron	Duraluminium	c. tin
4. magnesium	Cast	d. carbon (much)

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