The elements are identified by its aomic number and they are placed in the periodic table in ascending order of atomic number.
There is one unique element for a given atomic number.
For example, atomic number 1 identifies Hydrogen and there cannot be another different element with the same atomic number.
All the elements with atomic numbers from 1 to 118 have been discovered. So, you know that there is not room for new products with atomic number equal or less than 118.
Ammonia isn't an element, it's a compound made by mixing the elements Nitrogen and Hydrogen in the Haber process. Therefore, it isn't on the periodic table
The answer is B I’m pretty sure
Answer:
Explanation:
Earth's atmosphere is composed of about 78% nitrogen, 21% oxygen, and one percent other gases. These gases are found in layers (troposphere, stratosphere, mesosphere, thermosphere, and exosphere) defined by unique features such as temperature and pressure.
