Is ammonia pure substance or mixture?​

ammonia is judged to be a pure element due to because it is regarded as  a compound. In Ammonia, the substances are nitrogen and hydrogen. So there are no additional substances, elements, etc to create it.

Hope this helps!

1.  The Nile River so important to the Ancient Egyptians because the ancient Egyptians could grow crops only in the mud left behind when the Nile flooded. So they all had fields all along the River Nile.

2. A. The Cataracts of the Nile are shallow lengths (or whitewater rapids) of the Nile River, between Khartoum and Aswan, where the surface of the water is broken by many small boulders and stones jutting out of the river bed, as well as many rocky islets.

B. Deltas are wetlands that form as rivers empty their water and sediment into another body of water, such as an ocean, lake, or another river. Although very uncommon, deltas can also empty into land. A river moves more slowly as it nears its mouth, or end.

3. Ancient Egypt and Mesopotamia are very different. Mesopotamia was built in between two rivers, while Egypt was built next to the Nile River. Mesopotamia had lush, green land, while Egypt was in the middle of a desert.

4. The Egyptians were protected from invaders due to their geographical features. For example, they had the Mediterranean Sea to the north along with the Nile Delta. This body of water blocks off land on the other side. ... Furthermore, the cataracts in the Nile to the south protected the Egyptians from lands below them.

You are very welcome :P

Feel free to give brainliest. '-'