The History of the Periodic Table
This arranges elements by their atomic number and the similarities in properties.
What is the periodic table?
These are the electrons in the outermost shell of an atom.
What are valence electrons?
These elements are in group 18 of the periodic table and are very stable because their neutral atoms contain enough valence electrons to fill their outermost shells.
If a neutral atom gains an electron, this would be its charge.
What is negative?
12.
What is two?
The columns in the periodic table are referred to as these.
What are groups?
When looking at an element on the periodic table, the period or row corresponds to this electron quantum number for the elements' valence electrons.
What is the main energy level?
These metals span the d-block of the periodic table and tend to be more stable than other types of metals in nature.
What are transition metals?
As atomic number increases, the size of electron clouds _______.
What is increases?
1,208,000.0
What is eight?
This law states that physical and chemical properties of elements are functions of the element's atomic number.
What is periodic law?
In reference to the elements' electron configuration, the first two groups in the periodic table are collectively called this.
What is the s-block?
These metals are found in group 1 and are highly reactive with water.
What are alkali metals?
A stable atom has this many electrons in its outer shell.
What is eight?
8.00 x 10^6
What is three?
He was the first scientist to group elements by similar characteristics, but his periodic table had many blank spaces.
Who is Mendeleev?
The elements found in the d-block are commonly known as this.
What are transition metals?
These elements are found in group 17 and tend to be found as compounds in nature, rather than in their elemental form.
What are halogens?
These two families very rarely follow any trends.
What is lanthanides and actinides?
78.8g Al x (1 mol Al/26.982g) x (6.022 x 10^23 atoms/mol)
What is three?
The f-block contains these two groups of elements.
What are lanthanides and actinides?
These two blocks are referred to as the "main-group" elements.
What are the s- and p-blocks?
These elements follow a stair-step to the right of the transition metals, and contain properties of both metals and non-metals.
What are metalloids?
This "group" of elements most commonly follows periodic trends.
What is "main-group" elements?
Finding an average: (93.23g + 92.42g)/2
What is four?