Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. + 18 others found this useful. Jack Bakhet. Edit. Share to: Chrishan Silva. 509,209 Contributions. I'm an undergraduate in Physical Sciences stream.
1 Two gases make up the bulk of the earth's atmosphere: nitrogen (), which comprises 78% of the atmosphere, and oxygen (), which accounts for 21%. 2  Various trace gases make up the remainder. 3  Based on temperature, the atmosphere is divided into four layers: the troposphere, stratosphere, mesosphere, and thermosphere.
Quick Answer. Earth's atmosphere, which is around 300 miles thick, is mainly made of nitrogen and oxygen, although there are many other trace substances in its composition. Trace substances make up only 1 percent of the bulk of the atmosphere while nitrogen (78 percent), oxygen (21 percent) and argon (1 percent) make up the rest.