Boron is element number 5, with the symbol B. Its name comes from borax, a substance containing boron. Yes, the same borax used to make slime.
Atomic number 510.81
BBoronホウ素 (hōso)
Symbol
B
Atomic weight
10.81
Place in the table
Period 2 · Group 13
Atomic weight from the Chemical Society of Japan, “Table of Standard Atomic Weights with Four Significant Figures (2026)”.
Named for borax
The symbol B comes from borax, the Latin word for borax, which goes back further to a Persian word meaning “white.” Boron was discovered in 1808.
Borax is made of sodium, boron, oxygen and water.
Slime and borax
Slime forms when an ingredient in laundry starch is linked together by borax dissolved in water. In a Terakoya science project, you change the amount of borax water and see how the slime’s firmness changes.
Boron is in the second row of Group 13. Directly below it is aluminium.
Think about it
Q1If you add more borax water, how do you think the slime will change?
Q2Why might the word “white” have become the source of this name?
Q3Boron and aluminium share a column. Do you think they are alike in any way?
There is no single right answer. Talking it over with someone at home is a good way to learn.
Did you know? — Besides boron, magnesium, calcium, barium and strontium were also discovered in 1808.