W = ${\mathrm{H}}_2\mathrm{O}$, X = NaCl, Y = ${\mathrm{H}}_2{\mathrm{SO}}_4$, Z = NaOH, Y + Z → X + W

Reaction between Y and Z is called

As per given information the compound Y is an acid where as the compound Z is a base. If the chemical reaction is happened between Y and Z then the products salt and water are produced as X and W respectively.

$\underset{\mathrm{y}=\mathrm{acid}}{{\mathrm{H}}_2{\mathrm{SO}}_4}\underset{\mathrm{Z}=\mathrm{bases}}{+2\mathrm{NaOH}}\to \underset{\mathrm{X}= \mathrm{salt}}{{\mathrm{Na}}_2{\mathrm{SO}}_4}+\underset{\mathrm{W}= \mathrm{water}}{{\mathrm{H}}_2\mathrm{O}}$