NET Chemistry MCQs

Avogadro's constant gives the number of entities in one mole.
The entities may be atoms, molecules, ions, or formula units.

Molar mass is numerically related to relative atomic or molecular mass.
Its common unit is g/mol.

An empirical formula shows the lowest integer ratio of elements.
It may differ from the molecular formula.

A molecular formula is a whole-number multiple of the empirical formula.
It applies to substances composed of discrete molecules.

Solutions are homogeneous mixtures.
Any sampled portion has approximately the same composition.

Heterogeneous mixtures contain distinguishable regions or phases.
Examples include sand in water and granite.

A physical change alters form or state without changing chemical identity.
Ice and liquid water are both H2O.

Chemistry examines what matter is made of and how it behaves.
It also studies energy changes accompanying chemical processes.

Matter includes solids, liquids, gases, and plasma.
It is composed of atoms, molecules, or ions.

An element cannot be broken down chemically into simpler substances.
Each element is identified by its atomic number.

Compounds have definite formulas and characteristic properties.
Their components can be separated only by chemical means.

Mixture components retain much of their individual identity.
They can often be separated by physical methods.