Unit 2 Atomic Theory and structure exam

Who first suggested the existence of atoms and called them "atomos"?

• Niels Bohr

• John Dalton

• Democritus

• Albert Einstein

Match each scientist with his model of the atom.

• Planetary model

• Niels Bohr

• Plum Pudding model

• John Dalton

• Nuclear Model

• Ernest Rutherford

• Electron Cloud mode

• Einstein, Hund and others

• Billiard Ball model

• J.J. Thomson

Democritus, Thomson, and Dalton believed that atoms were not divisible.

• True

• False

Which atomic theorist proposed an atomic theory with 5 statements?

• Ernest Rutherford

• Albert Einstein

• James Chadwick

• John Dalton

Which statements from Dalton's Atomic Theory NO LONGER hold true today? (Select all that apply)

• All elements are composed of tiny indivisible particles called atoms.

• Atoms of the same element are identical in size, mass, and other properties.

• Atoms cannot be subdivided, created, or destroyed.

• Atoms of different elements can physically mix together or can be chemically combined in simple whole-number ratios to form compounds.

• Atoms can be combined, separated, or rearranged in chemical reactions, and atoms of one element, are NEVER changed into atoms of another element as a result of a chemical reaction.

J.J. Thomson used cathode ray tubes fitted with positive and negative poles to discover what particles?

• Neutrons

• Protons

• Electrons

• Quarks

Which of the following is the best description of J.J. Thomson's model of the atom?

• a featureless, indivisible sphere

• a sphere of positive material with electrons embedded in it

• mostly empty space with electrons randomly orbiting around a positive nucleus

• mostly empty space with electrons located in set orbits around a positive nucleus.

Thomson's model of the atom is called

• Billiard Ball model

• Plum Pudding model

• Planetary model

• Electron Cloud model

​ (a)   performed the ​ (b)   experiment and discovered that an atom's mass is concentrated in the ​ (c)   , surrounded by lots of empty space.

​

• Niels Bohr
• Cathode Ray Tube
• Ernest Rutherford
• Gold Foil
• nucleus
• nuclear

Reorder the following (from oldest theory to newest)

• Niels Bohr and Planetary model

• John Dalton and Billiard Ball model

• Ernest Rutherford and Nuclear model

• J.J. Thomson and Plum Pudding model

• Albert Einstein and Electron Cloud model