原子序数为 24 的原子,其外层电子构型是 ( ) A 、 3d 5 4s 2 B 、 4s 2 3d 4 C 、 3d 5 4s 1 D 、 4s 1 3d 5 2.决定核外电子运动状态的量子数是 ( ) A 、 n, l B 、 n, l, m C 、 n, l, m, m s D 、 n, l, m s 3、 C 原子外层电子构型为 ,单电子数为 ,它以 杂化轨道和 H 结合成 CH 4 分子, CH 4 分子的空间构型为 , CH 4 分子 (填“有”或“无”)极性。
【单选题】A nocturnal(夜间活动的)moth has become the first animal known to see colours in the dead of night. The moth uses this visual talent to find yellow, nectar-packed flowers in the dark, but the finding sugges...
【简答题】理解下列词组的意思,并用其填空 face value; conservative tastes; heavy make-up; bright colours; correct tone; highbrow subject; popular belief; 1 Both of us have rather ___________________, so we're unlikely to buy ...