Chemistry College Prep Final

Who developed a periodic table of the known elements in the late 1800s?

• Henry Moseley

• John Dalton

• Dmitri Mendeleev

• Marie Curie

What did Mendeleev notice when he arranged elements in order of increasing atomic mass?

• Elements became radioactive

• Similarities in chemical properties appeared in regular intervals

• Elements lost their properties

• Elements changed color

What was a major problem with Mendeleev’s periodic table?

• It did not include any metals

• Some elements had to be placed out of order of atomic mass to group similar properties

• It was arranged by atomic number

• It only included gases

Who extended Mendeleev’s arrangement of the periodic table by ordering the elements by atomic number?

• Dmitri Mendeleev

• Henry Moseley

• Albert Einstein

• Niels Bohr

What does the Periodic Law state?

• All elements are metals

• The physical and chemical properties of the elements are periodic functions of their atomic numbers

• Elements are arranged by color

• All elements have the same number of protons

What do elements in the same group have in common?

• The same number of protons

• The same number of valence electrons and similar chemical properties

• The same atomic mass

• The same color

What are valence electrons?

• Electrons found in the nucleus

• Electrons found in the innermost energy level

• Electrons found in the outermost energy level of atoms

• Protons in the outer shell

How is the number of valence electrons in main group elements determined?

• By the atomic mass

• By the period number

• By the group number or group number minus 10

• By the number of neutrons

What determines the length of each period in the periodic table?

• The number of protons in the nucleus

• The number of electrons that can occupy the sublevels being filled in that period

• The number of neutrons in the atom

• The color of the element

How many naturally occurring elements are there?

• 18

• 7

• 92

• 118