Chapter 4

In the late 1800s, who discovered a set of patterns that applied to all of the elements?

Silicon is the most common...

Which family does not react with other elements?

Our modern periodic table is arranged according to...

How many valence electrons does group 2 have?

It takes almost how many electrons to equal the mass of a proton or neutron?

How many vertical columns(families) are there?

Number of protons in the nucleus of the atom

Group 1 Name

Material can be hammered or rolled into flat sheets or other shapes

The atmosphere is almost what % nitrogen?

In 1913, he showed that electrons could have only certain amounts of energy moving in "orbits."

From left to right, the properties of the elements change in a pattern within a...

These are used to make semiconductors due to their varying ability to conduct electricity

Atoms with the same number of protons but different number of neutrons

In 1932, James Chadwick discovered the...

Where are the metals located in the periodic table?

Groups 3-12

Nonmetals

How many more valence electrons does group 16 need to become stable?

Top row of the bottom 2 rows on the table

Gold foil experiment

Group 17 (Halogens) needs how many more valence electrons to become stable?

In 1897, he found that atoms contain negatively charged particles. "Muffin Model"

Most abundant element in the earth's crust and second most abundant in the atmosphere

Which element is alone in the upper left corner and has one proton and one electron?

Group 15 has how many valence electrons?

Most reactive nonmetal family

Sum of the protons and neutrons in the nucleus

Around 430 B.C., he proposed that matter is formed of small pieces that could not be cut into smaller parts