GAT Subject Chemistry MCQs

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

Atomic number identifies the element.
In a neutral atom it also equals the number of electrons.

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

Mass equals moles multiplied by molar mass.
2×58.5 = 117 g.

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.

Actual yield is measured after the experiment.
It is usually lower than theoretical yield.

Percent yield measures reaction and recovery efficiency.
Values below 100% commonly result from losses or incomplete reaction.

Molarity is a common concentration unit.
Its value changes with temperature because solution volume can change.

Molality is based on solvent mass.
It is largely independent of temperature.