Development of the Atoms

Aristotle

________ suggested that everything was composed of 4 elements such as water.

Robert Millikan

________ found out that an electron has a charge of 1.6022* 10^- 19 coloumbs.

Alchemy

________ is the act of changing one substance to another.

Henry Gwyn Jeffreys Moseley

________ argued and confirmed that the basis for the arrangement in the periodic table is the atomic no.

Joseph John Thompson

________ is a British Scientist who discovered electrons in 1897 which lead to his "plum pudding model.

Democritus

________ believed that all matter has very small particles called atoms.

Compounds

________ are composed of atoms of more than one element.

Ernest Rutherford

________ discovered protons in 1919.

chemical reaction

In a(n) ________, atoms can neither be created nor destroyed.

Antoine Becquerel

________ accidentally learned that the darkening of thickly- wrapped photographic plates occurs after exposing them to uranium compounds.

Radioactivity

________ is the ability of a material to undergo spontaneous emission of particles or radiation.

Bohrs

In ________ model of an atom, the electron moves and stays in a particular, circular orbit at fixed distances from the nucleus where they do not lose or gain energy.

Leucippus

________ is known as the first atomist.

Erwin Schrodinger

________ developed mathematical equations to describe the motion of electrons in atoms which resulted in the electron cloud model.

Thales

________ believed that water is the ultimate substance that constituted matter.

James Chadwick

________ proved the presence of a neutron.

atom

An _____ is defined as the tiniest particle of an element that retains the chemical properties of that element.

elixir of life

The ________ was thought to bring wealth, health, and immortality.

Aether

________ is where stars are made from.

mythical concepts

The goals of alchemists consist of intertwined spiritual and ________ to transmute base metal to gold, discover a universal cure for diseases, and discover means of prolonging life.

1\.6022\* 10^- 19

A proton has a(n) magnitude charge of ______ coloumbs.

proton

A(n) ________ is a positively charged particle in a nucleus.

neutral, stable

In 1913, Niels Bohr proved the stability of particles, that the equal no. of protons and neutrons will make an atom electrically __________ and ______.

Marie Curie

________ proposed the term radioactivity.

Elements

________ are made up of small indivisible particles called atoms and they can neither be created nor destroyed during a chemical change.

Greek

Atoms are derived from the ________ word "atomos "meaning "indivisible "or "uncuttable.

Dmitry Mendeleev

________ arranged the elements according to atomic masses, he paved the way for the creation of the present periodic table.

nucleus

The nucleus is the central part of an atom.

ancient greeks

The ________ and the emergence of alchemy are the two historical periods that played an important role in the development of the atomic theory.

atom’s mass

A nucleus contains most of a(n) ________.

philosophers stone

The ________ was thought to be the highest and purest form of matter.

neutron

A(n) ________ is slightly heavier than a proton.

Beta decay

________ is deflected by a negatively charged plate.

nucleus

A(n) ________ is composed of protons and neutrons, which are both collectively called nucleons.

John Dalton

________ is known to be the pioneer in the development of modern atomic theory.

Chadwick

________ concluded that the radiation consisted of neutral particles that are slightly heavier than the protons but are found with the protons inside the nucleus.

isotope

An _____ is an atom of the same element but w different mass numbers.

model

The plum pudding ________ shows electrons being embedded in a sphere of positive electrical charge.

gold foil experiment

The ________ established that the nucleus is very dense, very small, and positively charged which resulted in Ernest Rutherford discovering protons.

Robert Boyle

________ wrote a book called "The Skeptical Chymist "in 1661 which resulted in scientists finding experimental results known as the atomic theory of matter.

Henry Gwyn Jeffreys Moseley

________ experimentally found that different metals bombarded with electrons produced varying frequencies of X- rays, which resulted to the differences in the positive charge in the nucleus of elements.

Atomism

________ is the philosophy for which all matter is produced from ________.

Gamma ray

________ has high energy and has no charge nor is affected by a magnetic field.

Boyle

According to ________, the elements water, fire, earth, and air are not true for they can still be broken down into iron, oxygen, lead, hydrogen, and sulfur.

1\.67262\* 10^24 grams

Each proton weighs as much as ________.

Thales of Miletus

________ is the first pre- Socratic philosopher (or in other words, a Classical Philosopher)

Ernest Rutherford

________ concluded that most of an atom is empty, which allowed most alpha particles to pass through a gold foil.

Erwin Schrodinger

In the ________ quantum mechanical model, instead of orbits, there were orbitals or regions of space with a high probability of finding electrons which are known as the electron clouds or electron subshells.

Democritus

________ is dubbed the "Father of Atomism.

Antoine Becquerel

________ started studying the fluorescent properties of substances after the discovery of X- rays in 1895 by Wilhelm Rontgen.

the atomic number

Mosely correlated the frequencies to whole numbers, which he assigned to each element. This is known as?