[tex]4NaOH _{(aq)} + ZnCl_{2}_{(aq)} ----\ \textgreater \ Na_{2}Zn(OH)_{4}_{(ppt)} + 2NaCl (aq) [/tex]
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[tex]mol = \frac{mass}{molar mass} [/tex]
∴  [tex]mol of ZnCl_{2} = \frac{2.00 g}{[(65)+(35.5 * 2)g/mol} [/tex]
                  =  [tex] \frac{2.00 g}{136 g/mol} [/tex]
                  =  0.0147 mol
[tex]Moles of Na_{2}Zn(OH)_{4} :[/tex]
[tex]ratio of ZnCl_{2} : Na_{2}Zn(OH)_{4} [/tex]
            1    :    1
∴ [tex]Moles of Na_{2}Zn(OH)_{4} [/tex] = 0.0147 mol
Mass = Molar Mass * Mol
∴ [tex]Mass of Na_{2}Zn(OH)_{4} [/tex] = [(23 * 2)+(65)+(16 * 4) + (1*4)] g/mol * 0.0147 mol
                            = 179 g/mol * 0.0147 mol
                            = 2.63 g