Nitrogen is element number 7, with the symbol N. About 80% of the air at ground level is nitrogen. It is also an important part of the fertilizers that help plants grow.
Atomic number 714.01
NNitrogen窒素 (chisso)
Symbol
N
Atomic weight
14.01
Place in the table
Period 2 · Group 15
Atomic weight from the Chemical Society of Japan, “Table of Standard Atomic Weights with Four Significant Figures (2026)”.
From “killing-source” to 窒素
In Dutch, nitrogen is stikstof. Udagawa Yōan first translated it as 殺素, “killing-source,” and later changed it to 窒素 (chisso).
The German word Stickstoff means “the stuff that suffocates.” The first character of 窒素 is the same character used in the Japanese word for suffocation, 窒息 (chissoku).
The symbol N comes from the Latin nitrogenium, made from words for “saltpeter” and “producing.”
In the air and in the fields
The air at ground level is almost all nitrogen and oxygen: 80% nitrogen and 20% oxygen. This mix stays the same up to a height of about 90 km.
The three main nutrients in fertilizer are nitrogen, phosphate and potassium. Nitrogen helps plants grow, especially their leaves.
Think about it
Q1Every time we breathe, we breathe in nitrogen too. What do you think happens to it?
Q2“Killing-source” or 窒素: which name would you choose, and why?
Q3Do vegetables we eat for their leaves need different fertilizer from vegetables we eat for their fruit?
There is no single right answer. Talking it over with someone at home is a good way to learn.
Did you know? — Many element names come from places, colors or properties. The N in nitrogen means “made from saltpeter,” and the O in oxygen means “acid-maker.” Both contain the idea of “producing.”