NET Applied Sciences MCQs

Molarity equals moles divided by liters of solution.
0.50/2.0 = 0.25 M.

Mole ratios convert amounts of one substance into another.
They come directly from the balanced equation.

Chemical reactions rearrange atoms but do not create or destroy them.
Therefore total mass remains constant in a closed system.

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.

Balancing follows conservation of atoms and mass.
Coefficients change amounts, not chemical formulas.

Equation coefficients give stoichiometric ratios.
They may be interpreted as molecule or mole ratios.

Once the limiting reactant is used up, no more product can form.
Other reactants may remain in excess.

An excess reactant is supplied beyond the stoichiometric requirement.
Some remains when the reaction is complete.

Theoretical yield assumes complete reaction and no losses.
It is calculated from the limiting reactant.