【简答题】称取含铝试样0.5000g,溶解后用8-羟基喹啉沉淀,得到0.3200gAl(C 9 H 6 NO) 3 沉淀,沉淀形式若为Al 2 O 3 ,可得到______g Al 2 O 3 沉淀物。
【单选题】A Windows Communication Foundation (WCF) service has a callback contract. You are developing a client application that will call this service.You must ensure that the client application can interact w...
A.
On the OperationContractAttribute, set the AsyncPattern property value to true.
B.
On the OperationContractAttribute, set the ReplyAction property value to the endpoint address of the client.
C.
On the client, create a proxy derived from DuplexClientBase .
D.
On the client, use GetCallbackChannel .
【多选题】自然主义早期教育理论的代表人物包括( )
【简答题】腔肠动物身体结构停留在胚胎发育的___________阶段。
【单选题】A Windows Communication Foundation (WCF) service is deployed with netTcpBinding. This service uses a duplex message exchange pattern.You are developing the next version of the WCF service. You discove...
B.
Create a custom binding that has the compositeDuplex, textMessageEncoding, and namedPipeTransport binding elements in this order.
C.
Create a custom binding that has the compositeDuplex, textMessageEncoding, and wsHttpTransport binding elements in this order.
【简答题】用高锰酸钾法测定锰矿石中的锰含量。称取均匀锰矿石样品0.5000g,加入0.8500g纯H 2 C 2 O 4 ˙2H 2 O,并加入足量的稀硫酸,加热反应完全后,用浓度为c(1/5KMnO 4 )=0.1000mol/L的高锰酸钾标准滴定溶液回滴剩余的草酸,消耗5.00ml,锰矿石中的MnO 2 的质量分数为()。
【简答题】称取含铝试样0.5000g,溶解后用8-羟基喹啉沉淀,得到0.3200gAl(C 9 H 6 NO) 3 沉淀。计算试样中铝的质量分数。沉淀形式若为Al 2 O 3 ,可得到多少克Al 2 O 3 沉淀物?[M(Al)=26.98g·mol -1 ,M(AlC 27 H 18 N 3 O 3 )=459.44g·mol -1 ,们(Al 2 O 3 )=101.96g·mol -1 ]