元素X、Y、Z原子序数之和为36，X、Y在同一周期，X＋与Z2－具有相同的核外电子层结构。下列推测不正确的是
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答案：B
考查元素周期表的结构和元素周期律的应用。X＋与Z2－具有相同的核外电子层结构，说明X是第IA碱金属，Z是第ⅥA元素，且Z位于X的上一周期，所以离子半径是X＋＜Z2－。X、Y在同一周期，因此Y在X的左侧，金属性比X的弱，原子半径小于X的。又因为元素X、Y、Z原子序数之和为36，所以X、Y、Z分别为Na、Cl、O。所以答案是B。
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| The white snow is calling you to the hills,lakes and ponds. 1 sports are cool. Keep some important safety tips(安全小贴士)inyour mind before 2 yourself outdoors. Safetytips forall 3 : Always keep yourself warm.Have some training lessons 4 you are new to a sport. Warm up before all sports. Make sure you are in good physical condition (身体状况). When 5 , wear your helmet. Always ski with a friend. 6 a hill far away from roads and parking lots. There should be no rocks or trees. Make sure your bindings are not too tight. 7 skating, never skate by yourself and don't skate too 8 to other people. Check your skating shoes before you 9 . If you skate on lakes or rivers, make sure the 10 is thick enough. Neverskate near open water. | |||
| ( )1. A. Spring ( )2. A. talking ( )3. A. facts ( )4. A. if ( )5. A. playing ( )6. A. Choose ( )7. A. What ( )8. A. young ( )9. A. clean ( )10. A. place | B. Summer B. fighting B. sports B. or B. skiing B. Stand B. How B. close B. make B. pool | C. Autumn C. enjoying C. clubs C. but C. skating C. Agree C. Why C. tired C. start C. water | D. Winter D. washing D. things D. so D. swimming D. Spend D. When D. happy D. say D. ice |