Vocabulary, & discoveries of chemistry. Flashcard

What is Dalton’s model for lead?
A circled ‘l’.
What is Dalton’s model for gold?
A circled ‘g’.
What is an elements atomic number?
The number of protons an element contains.
What is an atom?
An atom is an indivisible particle.
What is an element?
An element is a pure substance made up of the same type of atom.
What is an elements mass number?
An elements mass number is it’s protons + it’s electrons.
What is an isotope?
An isotope is an unstable atom with a different number of protons.
Who were the scientists that contributed to major elemental research? (in order from first to last).




Becquerel, Curie, Rutherford







How did Democritis contribute to the timeline?

He had the first coherent atomic theory, that matter could not be divided indefinitely.

*led to the idea of atoms.

How did John Dalton contribute to the timeline?

Dalton created the first modern atomic theory, refered to as the “Billiard ball” model which stated that atoms are solid and indivisible.


Based this model on experimentation instead of reason.

-All matter is made of atoms.

– Each element has different atoms.

– Atoms of an element are identical.

– Atoms of different elements combine in constant ratios to form compounds.

– Atoms are rearranged in reactions.

How did Becquerel, and Curie contribute to the timeline?
They were one of the first to discover radioactivity.
How did Ernest Rutheford contribute to the timeline?

Rutheford was one of the first to discover radioactivity.

He also identified an atom’s nucleus,

confirmed the proton existed,

and proposed the neutron exisited.

How did JJ Thompson contribute to the timeline?

Thompson discovered the positive charge in the nucleus.

He also discovered the electron.


*Developed the “Plum Pudding model” that showed that negative electrons in a positive framework.

How did Rutheford and Geiger contribute to the timeline?
They identified the atom and nucleus.
How did RA Miliken contribute to the timeline?
He determined the mass of electrons.
How did Moseley contribute to the timeline?
Moseley determined the atomic number of the elements.
How did Chadwick contribute to the timeline?
Chadwick identified the neutron.
How did Bohr contribute to the timeline?
Bohr delveloped the model self-titled “Bohr’s model” which represents an atom’s structure.

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