The periodic table is a catalog of all the different sorts of what?
atoms
Who was the boy that became the crown jewel of Russian science?
Dmitri Mendeleev
What is the second column of the periodic table known as?
Alkaline Earth Metals
On the far left, we have the soft, shiny, what metals?
Alkali Metals
What is the atomic number for oxygen?
8
How many elements were known to mankind in the 1800s?
About 60
Mendeleev found that the periodicity of the numbers was not working because...
Some atoms were not discovered yet.
Are the Alkali metals highly reactive or non-reactive?
Highly reactive
Alkaline Earth Metals are...
Reactive, but not as reactive as Alkali Metals.
How many neutrons does an atom of phosphorus contain if it has a mass number of 31?
16
The simplest way to sort the elements on the periodic table was by their what?
Atomic Weight
What did Mendeleev create for other scientists?
A guide for future chemical and scientific discoveries.
Are the Noble Gases reactive?
No
What properties do transition metals have?
They are shiny, malleable, good conductors of heat and electricity, and ductile.
An atom of strontium (Sr) contains 50 neutrons and 40 electrons. What is the net charge?
2+
The periodicity of elements is a what phenomenon?
Chemical
It was later found that there was a relationship between atomic weights, but it is considered what?
Periodic (regular and predictable)
Where are the Noble Gases located on the periodic table?
The last column
Halogens are elements that like to form what?
Anions (ions with a negative charge)
Atoms of the same element that have different numbers of neutrons are known as what?
Isotopes
Is the periodic table of elements "set in stone" (complete and never changing)?
No, new elements are still being discovered.
Do the Lanthanides and Actinides (bottom two rows) belong within the periodic table?
Yes, the periodic table is really wide.
The rectangle between the Halogens and the Transition Metals contains what?
Metals, metalloids, gases, and non-metals.
Describe the elements at the very bottom (Lanthanides and Actinides)
Similar and hard to separate.
Protons and neutrons are found in the nucleus, whereas the electrons are found in the what?
Electron cloud