Exploring the Periodic Table

Who was the first scientist to arrange elements in order of increasing atomic mass, leading to the early development of the periodic table?

• John Dalton

• Johann Döbereiner

• Dmitri Mendeleev

• Henry Moseley

What was the main feature of Mendeleev’s periodic table that made it different from earlier attempts?

• Arranged elements by atomic number

• Left gaps for undiscovered elements

• Grouped elements by colour

• Used alphabetical order

Which scientist is credited with determining the atomic number, leading to the modern arrangement of the periodic table?

• Dmitri Mendeleev

• Henry Moseley

• John Newlands

• Antoine Lavoisier

In the modern periodic table, elements are arranged in order of increasing:

• Atomic mass

• Atomic number

• Density

• Melting point

Which of the following is NOT a method used to classify elements in the periodic table?

• Metals, non-metals, and metalloids

• Groups and periods

• State of matter at room temperature

• Alphabetical order

What is the name given to the vertical columns in the periodic table?

• Periods

• Groups

• Rows

• Blocks

Which of the following statements about Mendeleev’s periodic table is TRUE?

• It was arranged by atomic number

• It predicted the properties of undiscovered elements

• It included all known elements at the time

• It was based on the number of neutrons

Which group in the periodic table contains the noble gases?

• Group 1

• Group 2

• Group 17

• Group 18

What is the main reason for the periodicity (repeating patterns) in the periodic table?

• Increasing atomic mass

• Similar electron configurations

• Similar densities

• Similar melting points

Which of the following is a metalloid?

• Sodium

• Silicon

• Oxygen

• Gold