Pakistan MCQs

The ground state is the most stable configuration.
Energy absorption can promote electrons to excited states.

Double bonds introduce bends into fatty-acid chains.
They often increase membrane fluidity.

Excited atoms can return to lower levels by emitting energy.
Atomic spectra arise from these transitions.

Double bonds introduce bends into fatty-acid chains.
They often increase membrane fluidity.

First ionization energy removes the first electron from a neutral gaseous atom.
Successive ionization energies remove additional electrons.

Double bonds introduce bends into fatty-acid chains.
They often increase membrane fluidity.

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

An anion forms when electrons are gained.
It has more electrons than protons.

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

Rutherford concluded that atoms contain a small dense positive nucleus.
Most atomic volume is empty space.

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.