GAT Subject Chemistry MCQs

Periodic trends arise from repeating valence-shell patterns.
The periodic table organizes these regularities.

Alkali metals have one valence electron.
They commonly form +1 ions and are highly reactive.

Halogens have seven valence electrons.
They commonly form -1 ions.

Noble gases have filled valence shells in their common ground states.
They are generally unreactive.

Increasing nuclear charge pulls electrons closer within the same main shell.
Effective nuclear attraction generally increases across a period.

Additional electron shells are added down a group.
This outweighs the increased nuclear charge.

Effective nuclear charge generally increases across a period.
Electrons are therefore harder to remove, with some exceptions.

Electron affinity reflects attraction for an added electron.
Its sign and magnitude vary across the periodic table.

Electronegativity helps predict bond polarity.
Fluorine has the highest common electronegativity.

Valence electrons largely determine chemical reactivity.
Elements in a group often share similar valence configurations.

Thomson's cathode-ray experiments revealed negatively charged particles.
He proposed an early model with electrons in positive matter.

Chadwick identified the neutral nuclear particle in 1932.
Neutrons explain isotopic mass differences.