[1] A 27.0 gram sample of an unknown hydrocarbon is burned in exess oxygen to form 88.0 grams of carbon dioxide and 27.0 grams of water. What is a possible molecular formula of the hydrocarbon? a. CH4 b. C2H2 c. C4H3 d. C4H6 e. C4H10 [2] The alkenes are compounds of carbon and hydrogen with the general formula CnH2n. If 0.561 grams of any alkene is burned in excess oxygen, what number of moles of H2O is formed? a. 0.0400 mole b. 0.0600 mole c. 0.0800 mole d. 0.400 mole e. 0.800 mole [3] A sample of 9.00 grams of aluminum metal is added to an excess of HCl. The volume of hydrogen gas produced at STP is a. 22.4 L b. 11.2 L c. 7.46 L d. 5.60 L e. 3.74 L [4] Which molecule exhibits sp3d2 hybridization? a. SO2 b. SF6 c. CH4 d. PCl5 [5] When carbon undergoes sp2 hybridization, it forms a. Four sigma bonds b. Three sigma bonds and one pi bond c. Two sigma bonds and two pi bonds d. One sigma bond and three pi bonds e. Four pi bonds [6] Which molecule has triangular bipyramid geometry? a. PF5 b. H2O c. SF6 d. PCl3 [7] The approximate OSO angle in the SO2 molecules is: a. 90 degrees b. 109 degrees c. 120 degrees d. 180 degrees