In discussing halogen reactivity (as covered in Core Idea), it is a common practice to argue that as you go down the Group 17 elements it becomes harder for the elements to gain an electron to form a ...

When the alkali metals react with the different halogens (Group 7 of the periodic table), the group of compounds formed are known as the alkali metals halides. Due to the fact that there are a ...

Introducing the periodic table is a way of saying, "This is our language ... Then at the other extreme there are the gases and halogens. The idea that the table shows us how to group similar elements ...

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 ...