(i) Ester functional group RCOOR(ii) The emperical formula is the simplest whole number ratio of atoms in a compound therefore C4H8O(iii) The molar mass is C (12 x 8) = 96 H (1 x 18) = 18 O (2 x 16) = 32Molar mass = 146g mol ^(-1)(iv) To find the moles of the compound you use the moles= mass/molar mass relationship1.5/146= 0.01 moles