Elements are classified into groups by their state of matter and into periods by their atomic number.

Elements are classified into groups by their color and into periods by their density.

Elements are classified into groups by atomic mass and into periods by chemical reactivity.

Elements are classified into groups by similar properties and into periods by the number of electron shells.

It serves as a guideline for the classification of organic molecules.

The periodic law is significant for predicting chemical reactions of compounds.

The significance lies in its historical context in the development of atomic theory.

The significance of the periodic law is that it provides a systematic framework for understanding the relationships between the properties of elements and their atomic structure.

The atomic radius increases across a period.

The atomic radius remains constant across a period.

The atomic radius fluctuates across a period.

The atomic radius decreases across a period.

Electronegativity remains constant down a group.

Electronegativity decreases down a group.

Electronegativity increases down a group.

Electronegativity fluctuates down a group.

Metals are transparent, lightweight, and have low melting points.

Metals are dull, non-malleable, and usually liquid at room temperature.

Metals are brittle, non-conductive, and gaseous at room temperature.

Metals are conductive, malleable, ductile, lustrous, dense, and usually solid at room temperature.

Nonmetals tend to lose electrons and have lower electronegativity compared to metals.

Nonmetals are characterized by high conductivity and electron loss, unlike metals.

Nonmetals are characterized by poor conductivity, higher electronegativity, and electron gain, unlike metals which are good conductors, have lower electronegativity, and lose electrons.

Nonmetals are excellent conductors and have low electronegativity, unlike metals.

1. Semiconductors of electricity 2. Metallic luster 3. Brittle in nature

Good conductors of heat

Malleable and ductile

Dull appearance

Electron configuration has no impact on an element's reactivity.

Electron configuration only influences the element's color and appearance.

The position is solely based on atomic mass and not electron arrangement.

Electron configuration affects an element's position by determining its chemical properties and grouping in the periodic table.

n^1p

ns^2

n^1s

ns^1

Periodicity describes the constant change in atomic size across the periodic table.

Periodicity is the unique arrangement of elements based on their atomic mass.

Periodicity is the recurring trends in chemical properties of elements based on their position in the periodic table.

Periodicity refers to the random distribution of elements in the periodic table.

Oxygen, Nitrogen, Carbon, Sulfur

Lithium, Sodium, Potassium, Rubidium

Chlorine, Fluorine, Bromine, Iodine

Helium, Neon, Argon, Krypton, Xenon, Radon

Ionization energy decreases across a period.

Ionization energy increases across a period.

Ionization energy remains constant across a period.

Ionization energy fluctuates across a period.

The group number indicates the atomic mass of an element.

Valence electrons are unrelated to the group number of an element.

The group number reflects the total number of electrons in an atom.

The group number corresponds to the number of valence electrons in the outer shell of an element.

Reactivity decreases down the group in alkali metals.

Reactivity increases down the group in alkali metals.

Reactivity increases up the group in alkali metals.

Reactivity remains constant down the group in alkali metals.

Catalysts in chemical reactions, Pigments in paints and dyes, Components in alloys (e.g., steel), Conductors in electronics, Biological roles (e.g., hemoglobin)

Adhesives in construction

Fertilizers in agriculture

Insulators in electrical systems

Halogens are stable gases, while noble gases are reactive nonmetals.

Halogens are metals, while noble gases are nonmetals.

Halogens are inert and stable, while noble gases are reactive nonmetals.

Halogens are reactive nonmetals, while noble gases are inert and stable.

1s² 2s² 2p⁵

1s² 2s² 2p⁴

1s² 2s² 2p²

1s² 2s² 2p³

The octet rule describes the physical properties of elements, not their reactivity.

The octet rule is significant as it explains the reactivity and bonding behavior of elements, guiding their classification in the periodic table.

The octet rule only applies to noble gases and has no broader significance.

The octet rule is irrelevant to the classification of elements in the periodic table.

Atomic size decreases, while reactivity and ionization energy remain stable.

Elements become less reactive, with increased ionization energy and electronegativity.

The properties of elements remain constant with no significant changes.

The properties of elements change by increasing atomic size, decreasing ionization energy and electronegativity, and increasing reactivity.