Unit 2 Flashcards-Atomic Structure, Atoms and Periodic Table

Front

Which of the following is NOT a postulate in Dalton's atomic theory?

Back

All matter consists of particles called atom that can be divided.

Front

What part of the atom was discovered as a result of JJ Thomson's cathode ray experiments?

Back

Electron

Front

Which statement correctly explains the composition of the nucleus of Rubidium-87?

Back

Rubidium-87 has 37 protons and 50 neutrons.

Front

Hydrogen has three isotopes: hydrogen, deuterium, and tritium with atomic masses of about 1 amu, 2 amu, and 3 amu, respectively. Considering the average atomic mass of hydrogen that appears on the Periodic Table, which statement is correct?

Back

The average atomic mass of an element is usually closest to that of the isotope with the largest amount on earth.

Front

Calculate the atomic mass of the unknown element X described below.

Isotope | Percent Abundance
204X | 1.37
206X | 26.26
207X | 20.82
208X | 51.55

Back

207 amu

Front

What did Ernest Rutherford use for his experiments to test atomic structure theory in the early 1800’s?

Back

Gold Foil Experiment

Front

What does the Bohr model contribute to the theory on the structure of the atom?

Back

Electrons are arranged in specific energy levels around the atom.

Front

Which of the following statements is most accurate regarding atoms?

Back

Atoms of the same element may have different mass numbers.

Front

What does the following hyphen notation of Helium-3 mean?

Back

An atom of Helium-3 has two protons, two electrons, and one neutron.

Front

What describes the properties of noble gases?

Back

They are generally unreactive.