若共轭体系
电子数符合4n+2，则该化合物具有芳香性。（）
电子数符合4n+2，则该化合物具有芳香性。（）
举一反三
- 下列羰基化合物分子中，既存在σ-π超共轭效应，又存在π-π共轭效应的是（） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/b037ba3cc4b845c6a7a89933bf438d98.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/46bc3c9d231349e091ffb48341727085.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/9d5bb2934ef240349846c4a3dcac3f2f.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/abecafc7ca9f4a83bd3c839cb61c8b21.png" >
- 已知某系统模拟图如图所示，则该系统数学模型为（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/7b331e776a454b34b3ce7514c85f55ce.png" ><img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/9b732439cb324b709c699aa7caf1bd43.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/3a6a819b0f204f1c861fa806fcff9bfa.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/296a376761a64a66a35f073904daa96f.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/6d22be023ff94910a3dc634670220912.png" >
- 若某系统的传递函数为G（s）=<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/40cffec1140048fda668f02b2697bfb6.png" >，则相应的频率特性G（jω）为（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/b0edaaca759a4b96b2746d371ba37485.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/17d6f581231244c386888754b3bf178d.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/e5485f9797b64853b91ce68c4697ff2e.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/5330c18e71b94abdbeaeff937486d18a.png" >
- 下列化合物中，不具有极性的是（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/547b09efddc44eafa464beb5043142a7.png"> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/042b473209bc447b8f7914e4efe318d2.png"> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/60e6fcf97d024d519962631efc7a0e83.png"> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/b06bf6679a754656b24920d3a7c120a0.png">
- 亲核性最强的是（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/57e2c03b54f14a0a92e58cccdd920371.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/5bbbbff9b4b54e25b0e14eae38022d71.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/2ab00707a09546a1a47e7f577da4e52b.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201912/c092dc5bfa7e40ada1ec10b39bc5ac52.png" >