Reactions and compounds. New substances are formed by chemical reactions. When elements react together to form compounds their atoms join to other atoms using chemical bonds. For example, iron and sulfur react together to form a compound called iron sulfide.Mixture of iron (grey) and sulfur (yellow) powders.hen elements react, their atoms join with other atoms to form compounds [compound: A compound is a substance formed by the chemical union (involving bond formation) of two or more elements. ] . Chemical bonds form when this happens, which involves atoms transferring or sharing electrons.
The 'red land' was the barren desert that protected Egypt on two sides. These deserts separated ancient Egypt from neighbouring countries and invading armies. They also provided the ancient Egyptians with a source for precious metals and semi-precious stones.
Mesopotamia vs Egypt. Mesopotamia and Egypt are two different civilizations that show some difference between them when it comes to their history and growth. Egypt was built on both the sides of the River Nile. On the other hand, Mesopotamia was built in the fertile area between Tigris and Euphrates River. This is the main difference between Mesopotamia and Egypt. Though the location of each civilization was different, they do share something is common. Both Mesopotamia and Egypt had access to water resources. So, it is believed that both these civilizations developed on the basis of water.