unit13reading课件
日期：2010-02-18 02:36
thatis，seawaterorpurewater?ASeawaterBPurewater9Putanicecubeinaglassofpurewater，whathappens?AOilfloatsonthewaterBWaterfloatsontheoilCTheymixtogether5Willchalkbedissolvedifyouputitintowater?AYesBNo6What’stheseawater?AIt’samixtureofdissolvedgasesandsolidswithfreshwaterBSeawaterislighterthanpurewater7Doestheseafreeze?AYesBNo8What’sheavier，whathappens?AItfloatsinthewaterBItsinks10Putanicecubeinaglassofsaltwater，Howmuchdoyouknowaboutwater?IndividualworkLet’shaveawaterQuiz!1Whatstateiswaterinatroomtemperature?AliquidBsolidCgas2Thechemicalstructureofwateris_____AtwohydrogenatomsandoneoxygenatomBtwooxygenatomsandonehydrogenatom3Thewatermoleculeispolar，ithas____AtwonegativeandonepositiveendBonenegativeandtwopositiveendsConenegativeandonepositiveend4Ifyoupourwaterandvegetableoilintooneglass，whathappens?AItfloatsonthewaterB，
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