[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fSqkgKR9RPfN7lDlkXnZIgVWWf-MuD_v2zZXClhwiwnI":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":12,"question":16,"related":17,"source":28,"type":29},[],"2023-11-10 09:56:49",104833285,[8,9,10,11],"pH=2","pH=5","pH=10","pH=12",{"courseId":13,"courseImg":14,"courseName":15},"80e84a6c1587aacb0dab697a3adf3ece","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fee882eee16e7a6f98687ae24bf57c536.jpg","分析化学","在Ca2+, Mg2+共存时,在下列哪个pH下,可不加掩蔽剂用EDTA直接滴定Ca2+?( )",[18,30,39,48,57,66,75,84,93,96],{"answer":19,"createTime":20,"id":21,"options":22,"question":27,"source":28,"type":29},[],"2023-11-10 09:56:48",104833259,[23,24,25,26],"控制溶液的酸度","掩蔽作用","解蔽作用","加入有机试剂","为了提高络合滴定的选择性,采取的措施之一是设法降低干扰离子的浓度,其作用叫做( )","v1",0,{"answer":31,"createTime":20,"id":32,"options":33,"question":38,"source":28,"type":29},[],104833262,[34,35,36,37],"于pH=10的氨性缓冲溶液中直接加入三乙醇胺","于酸性溶液中加入KCN,然后调至pH=10","于酸性溶液中加入三乙醇胺,然后调至pH=10的氨性溶液","加入三乙醇胺时,不需要考虑溶液的酸碱性","在用EDTA测定Ca2+、Mg2+的含量时,消除少量Fe3+、Al3+干扰的下述方法中,哪一种是正确的( )",{"answer":40,"createTime":20,"id":41,"options":42,"question":47,"source":28,"type":29},[],104833266,[43,44,45,46],"1. 9 ~ 12.2","< 1.9","=12.2",">12.2","已 知 某 金 属 指 示 剂 的 颜 色 变 化 和 pKa 值 如 下 :\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fe56fcd2591a8d2319d01f0e7078be687.png\"> 该 金 属 指 示 剂 与 金 属 离 子 形 成 的 配 合 物 为 红 色, 则 它 在 配 位 滴 定 时 适 用 pH 范 围 是",{"answer":49,"createTime":20,"id":50,"options":51,"question":56,"source":28,"type":29},[],104833271,[52,53,54,55],"0.1 左 右","0.22 ~ 0.45","0.45~ 0.85","1.2 ~ 2.4","以EDTA滴定石灰石CaO含量时,采用 0.02 mol\u002FL\u002FEDTA 溶 液 滴定. 设试样中含 50% CaO, 试样溶解后定容250mL , 移 取 25 mL 进行滴定. 则试样称取量 (单位 : g ) 宜为 : ( )( 已 知 MCaO = 56.08 g\u002Fmol)",{"answer":58,"createTime":20,"id":59,"options":60,"question":65,"source":28,"type":29},[],104833274,[61,62,63,64],"在酸度较高的溶液中,可形成MHY络合物","在碱性较高的溶液中,可形成MOHY络合物","不论形成MHY或MOHY,滴定反应进行的程度都将增大","不论溶液pH值的大小,只形成MY一种形式络合物","以EDTA为滴定剂,下列叙述错误的是( )",{"answer":67,"createTime":20,"id":68,"options":69,"question":74,"source":28,"type":29},[],104833277,[70,71,72,73],"10%","10.1%","10.08%","10.077%","测定试样中CaO的质量分数,称取试样0.9080 g,滴定耗去EDTA标准溶液20.50 mL,以下结果表示正确的是 ( )",{"answer":76,"createTime":20,"id":77,"options":78,"question":83,"source":28,"type":29},[],104833280,[79,80,81,82],"Ca2+的含量","Mg2+的含量","Ca2+, Mg2+总量","Ca2+, Mg2+, Fe3+, Al3+总量","某溶液中含Ca2+, Mg2+及少量Fe3+, Al3+,现加入三乙醇胺,并调节溶液pH=10,以EBT为指示剂,用EDTA标准溶液滴定,此时测得的是( )",{"answer":85,"createTime":5,"id":86,"options":87,"question":92,"source":28,"type":29},[],104833283,[88,89,90,91],"增大","趋于0","趋于∞","迅速下降","当pH>12时,EDTA的lgαY(H)将( )",{"answer":94,"createTime":5,"id":6,"options":95,"question":16,"source":28,"type":29},[],[8,9,10,11],{"answer":97,"createTime":5,"id":98,"options":99,"question":104,"source":28,"type":29},[],104833287,[100,101,102,103],"\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F87ceddaef61d4815e2fe5a351520362e.png\">","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F04a1983624c3cf08f6d1888e99a5aa15.png\">","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F324df2671d3376b2682ccd9edb4de77c.png\">","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fd2cd4c7b90750cb3f6def0bcfa4f5c59.png\">","下列表达式中,正确的是( )"]