来自MSN1 个月
118 Elements and Their Symbols and Atomic Numbers: Definition, Symbol with Atomic Number
There are 118 elements in the periodic table, each with a unique symbol and atomic number. Symbol: A one or two-letter abbreviation used to represent the element. Atomic number: The number of ...
BBC3 年
The modern periodic table
This is made of aluminium. Aluminium is an element. Now, each element has a chemical symbol made of one or two letters. Cal: Right, OK. And what is the chemical symbol for aluminium? Mrs Roberts ...