What is the main criterion for arranging elements in the periodic table?

• Increasing atomic mass

• Increasing neutron number

• Increasing proton number

• Increasing electron affinity

What is a group in the periodic table?

• A vertical column of elements

• A series of elements with the same atomic mass

• A block of elements with similar properties

• A horizontal row of elements

What is the electronic configuration of magnesium (Mg)?

• 1s2 2s2 2p6 4s2

• 1s2 2s2 2p6 3s2

• 1s2 2s2 2p6 3s1

• 1s2 2s2 2p6 3s3

What happens to atomic radii as you move down a group?

• They fluctuate

• They increase

• They remain constant

• They decrease

What is the trend in ionization energy as you move across a period?

• It decreases

• It increases

• It remains the same

• It fluctuates

Which of the following ions is larger?

• Si4+

• Na+

• Mg2+

• Al3+

What is electronegativity?

• The energy required to remove an electron

• The tendency of an atom to attract electrons

• The number of protons in an atom

• The size of an atom

Which halogen is the most reactive?

• Fluorine

• Chlorine

• Bromine

• Iodine

What is the result of adding silver nitrate to a chloride solution?

• Yellow precipitate of silver iodide

• White precipitate of silver chloride

• No reaction

• Cream precipitate of silver bromide

What is the effective nuclear charge (Zeff)?

• The total number of protons in the nucleus

• The net positive charge experienced by valence electrons

• The number of neutrons in the nucleus

• The charge of the nucleus