The Periodic Table

What significant contribution did Dmitri Mendeleev make to the periodic table in 1869?

• He classified elements based on their chemical reactivity.
• He discovered the atomic number of elements.
• He published a periodic table that arranged elements by atomic weight.
• He created the first atomic model.

What was a notable feature of Mendeleev's periodic table?

• It arranged elements in alphabetical order.
• It included all known elements at the time.
• It left gaps for undiscovered elements and predicted their properties.
• It was based solely on the atomic number of elements.

How did Mendeleev's periodic table categorize elements?

• By their electron configurations.
• By grouping elements with similar properties into columns.
• By their physical states at room temperature.
• By their atomic mass only.

What discovery did Henry Moseley make in 1913 that changed the periodic table?

• He discovered the neutron.
• He discovered the atomic number.
• He discovered the electron.
• He discovered isotopes.

What did Moseley's experiments demonstrate regarding the arrangement of elements?

• Elements should be arranged by their atomic weight.
• Elements should be arranged by their chemical properties.
• Elements should be arranged by their atomic number instead of atomic weight.
• Elements should be arranged randomly.

How many confirmed elements are in the modern periodic table?

• 118
• 150
• 92
• 63

What organizational structure does the periodic table use?

• Random arrangement.
• Both periods and groups.
• Only periods.
• Only groups.

What characteristic do elements in the same group of the periodic table share?

• They exhibit similar chemical behaviors.
• They have the same atomic weight.
• They are all metals.
• They have the same number of protons.

In which fields has the periodic table had a significant influence beyond chemistry?

• Only biology.
• Only physics.
• Only environmental science.
• Biology, physics, and environmental science.

Why is the periodic table considered a vital educational tool?

• It is only useful for advanced chemistry students.
• It introduces students to fundamental concepts of science.
• It is primarily a historical document.
• It is used only in laboratory settings.