Sir William Crookes and His Contribution to Atomic TheoryBY BRODY DONALDSON

Date of Birth

June 17th, 1832The Institution of Engineering and

Technology. "Sir William Crookes." N.p., n.d. Web. 1 Dec. 2014. <http://www.theiet.org/resources/library/archives/biographies/crookes.cfm>

The Chemical News is Founded

Sir William Crookes first published this magazine in the year 1859, he continued to publish it until 1906.

In this magazine he would later publish his new findings.

The Institution of Engineering and Technology. "Sir William Crookes." N.p., n.d. Web. 1 Dec. 2014. <http://www.theiet.org/resources/library/archives/biographies/crookes.cfm>.

Discovery of Thallium In 1861 Crookes discovered this new element

through spectroscopic methods. Thallium was discovered accidentally while

Crookes was looking for something else. National High Magnetic Field Laboratory.

"William Crookes." N.p., n.d. Web. 1 Dec. 2014. <http://www.magnet.fsu.edu/education/tutorials/pioneers/crookes.html>.

Atomic Weight of Thallium

In 1873 Crookes made his final determination on the atomic weight of his newly discovered element.

Encyclopædia Britannica. "Sir William Crookes." N.p., n.d. Web. 2 Dec. 2014. <http://www.britannica.com/EBchecked/topic/143944/Sir-William-Crookes>

Characteristics of Cathode Rays Crookes discovered new characteristics of

cathode rays in the year 1879. He found that…

1. They travel in straight lines.

2. They cause glass to fluoresce.

3. They impart a negative charge to the objects they strike.

4. Electric and magnetic fields deflect them, suggesting a negative charge.

Buescher, Lee. "Atomic Structure Timeline." N.p., n.d. Web. 2 Dec. 2014. <http://atomictimeline.net/index.php>

Crookes Dark SpaceCrookes also observed the dark space

around cathode rays.Encyclopædia Britannica. "Crookes Dark

Space." N.p., n.d. Web. 2 Dec. 2014. <http://www.britannica.com/EBchecked/topic/143949/Crookes-dark-space>.

A Spinthariscope is Developed In 1903 Crookes developed this device, used for the

study of alpha particles. The spinthariscope allowed for the viewer to see

matter decay. Oak Ridge Associated Universities. "Crookes

Spinthariscope." N.p., n.d. Web. 2 Dec. 2014. <http://www.orau.org/ptp/collection/spinthariscopes/crookes.htm>.

Date of Death

April 4th, 1919The Institution of Engineering and

Technology. "Sir William Crookes." N.p., n.d. Web. 1 Dec. 2014. <http://www.theiet.org/resources/library/archives/biographies/crookes.cfm>