Question

26. Aluminum oxide, Al:O, is used as a filler for paints and varnishes as well as in the manufacture of electrical insulators. Caleulate the mumber of moles in 47.51 g of Al:O A) 2.377 mol B) 2.146 mol C) 1.105 mol ) 0.4660 mol E) 0.4207 mol 27. Calculate the molar mass of rubidium carbonate, Rb COs. A) 340.43 g/mol B) 255.00 g/mol &) 230.94 g/mol D) 145.47 g/mol E) 113.48 g/mol 28. Calculate the molar mass of tetraphosphorus decaoxide, P4O10, a corrosive substance which can be used as a drying agent. A) 469.73 g/mol B) 283.89 g/mol 190.97 g/mol D) 139.88 g/mol E) 94.97 g/mol 29. Balance the following equation: HF(D 2HF() 4HF() HaFa() 4HF(D UF4(s) HzO(D) UF4(s) H20() UF4(s) UF (s) UO2(s) A) UO2(s) B UO2(s) C) UO2 (s) D) UO2(s) E) UO(s) 8HF(I) + 2H2O() H&O2() -> + + +4H2O( UF&(s) -> 2UF (s) 4H2O() 30. Ammonia will react with fluorine to produce dinitrogen tetrafluoride and hydrogen fluoride (used in production of aluminum, in uranium processing, and in frosting of light bulbs). 2NH (g) How many moles of NH3 are needed to react completely with 13.6 mol of F2? 6HF(g) N2F&(g) + SF2(g) A) 34.0 mol B) 27.2 mol C) 6.80 mol D) 5.44 mol E) 2.27 mol Page 6