Chemistry Atomic Theory Quiz

Democritus

first theorist of atoms

Democritus

based on philosophy not experiments

Democritus

stated that properties are a result of differently shaped and sized atoms

Dalton

atoms are conceived of as invisible particles that cannot be created nor destroyed

Dalton

atoms are rearranged in whole number ratios during chemical reactions

Thomson

used cathode ray tubes to discover the existence of negatively charged electrons inside the atoms

Thomson

disproved Dalton’s 1st postulate

Thomson

he proposed that negative electrons are embedded in a positively charged matrix

Rutherford

conducted the gold foil experiment which proved the existence of a positively charged nucleus at the center of the atoms

Rutherford

proved that atoms are mostly empty space

Rutherford

determined the nucleus was composed of positively charged protons

Bohr

determined that electrons are located in shells or energy level at varying distances from an atom’s nucleus

Chadwick

discovered the existence of the neutron

Chadwick

solved the extra mass problem of isotopes by discovering the existence of the neutron and laying the groundwork for nuclear fusion

dalton’s model

solid sphere model

Thomson’s model

plum pudding model

Rutherford’s model

nuclear model

Bohr’s model

planetary model

incorrect postulate 1

all atoms of the same element are identical and have the same weight

correct postulate 1

matter consists of large number of tiny particles called atoms

correct postulate 2

chemical reactions involve the combination, separation, or rearrangement of atoms, but atoms are neither created, destroyed, divided into parts, or converted into atoms of any other kind.

correct postulate 3

atoms combine to form molecules in fixed ratios of small whole numbers

incorrect postulate 2

atoms of an element cannot be created, destroyed, or broken into smaller parts or transformed into atoms of another element

Democritus

given credit for coining the term “atom”

Dalton

given credit for developing first modern atomic theory

Schrodinger

electron cloud theory

Rutherford

gold foil experiments