Crash Course Chemistry: The Periodic Table

What motivated Dmitri Mendeleev to achieve greatness in his scientific career?

• The rejection from the university in Moscow

• His father's profession as a professor

• His early interest in glassmaking

• His mother's sacrifices

Which group of elements did Mendeleev find to be extremely reactive with chlorine, fluorine, iodine, and bromine?

• Alkali metals

• Alkaline earth metals

• Noble gases

• Transition metals

What was Mendeleev's key realization that led to the development of the periodic table?

• Elements could be organized by their color

• Elements showed periodicity when arranged by atomic weight

• Elements were all metals

• Elements could be grouped by their state at room temperature

How did Mendeleev handle the discovery of elements that did not fit his periodic table?

• He removed those elements from his table

• He revised the atomic weights of known elements

• He ignored them

• He inserted gaps for undiscovered elements

What was unique about Mendeleev's approach to the periodic table compared to his contemporaries?

• He predicted the existence and properties of undiscovered elements

• He organized elements by their atomic number

• He believed in the mystical properties of elements

• He focused on the elements' colors

What characteristic is common among the alkali metals?

• They are stored in inert gases or oil

• They are poor conductors of electricity

• They are non-reactive

• They form negative ions

Which set of elements forms cations with two positive charges?

• Alkali metals

• Alkaline earth metals

• Transition metals

• Noble gases

Which group of elements did Mendeleev predict would be discovered to fill the gaps in his periodic table?

• Halogens

• Alkali metals

• Noble gases

• Lanthanides and actinides

What was the primary reason Mendeleev's periodic table gained acceptance over others?

• It was published first

• It included more elements

• It was easier to understand

• It accurately predicted properties of undiscovered elements

What fundamental particle's discovery answered the 'Why?' behind the periodic table's structure?

• Proton

• Neutron

• Electron

• Photon