Atomic Structure and Periodicity Quiz

Who proposed the first atomic theory?

• Dalton

• Thomson

• Democritus

• Aristotle

What did Dalton's atomic theory state about atoms?

• Atoms are all different

• Atoms can be destroyed

• Atoms are indivisible

• Atoms are created in chemical reactions

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

• Atoms are indivisible

• Atoms of the same element are identical

• Atoms can be created

• Compounds are formed from atoms

What are isotopes?

• Atoms with the same number of protons but different masses

• Atoms that cannot exist in nature

• Atoms with different numbers of protons

• Atoms with different chemical properties

Who discovered the electron?

• Dalton

• Rutherford

• Thomson

• Chadwick

What is the charge of an electron?

• Neutral

• Negative

• Variable

• Positive

What type of radiation is emitted by radioactive isotopes?

• Gamma rays

• Beta particles

• All of the above

• Alpha particles

Who discovered the atomic nucleus?

• Bohr

• Rutherford

• Chadwick

• Thomson

What is the mass of a neutron compared to a proton?

• Variable

• More than a proton

• Equal to a proton

• Less than a proton

What is the atomic number of an element?

• Number of neutrons

• Sum of protons and neutrons

• Number of protons

• Number of electrons