You need to calculate the molar mass for Al(CN)3 using the atomic weights for Al, C, and N given on the periodic table.
1 Al (26.98) + 3 C (3 x 12.01) + 3 N (3 x 14.01) = 105.04 g Al(CN)3 / mole
183 g Al(CN)3 x (1 mole Al(CN)3 / 105.04 g Al(CN)3) = 1.74 moles Al(CN)3
