【简答题】The ( ) of an atom is a number that represents the electric charge that the atom would have if the electrons in a compound were assigned to the atoms in a certain conventional way.
【单选题】In a compound, the______element of the compound determines the new word class.
【简答题】第二次妇女运动开始于20世纪60年代中期,运动的基调就是要消除()。
【判断题】反倾销税是对实行倾销的出口商征收的一种进口关税。
【简答题】在 的氨性缓冲溶液中,若Al 3+ 和Mg 2+ 的起始浓度均为1.0×10 -2 mol·dm -3 ,问此时能否将两离子定量分离?已知K sp (Al(OH) 3 )=1.3×10 -33 ,K sp (Mg(OH) 2 )=1.3×10 -11 ,K b (NH 3 )=1.8×10 -5 。
【单选题】在下列两种情况下,以EDTA滴定同浓度的 :一是在pH=10的氨性缓冲溶液中;二是在pH=5.5的六亚甲基四氨缓冲溶液中。滴定之前,对pZn值的大小叙述正确的是哪一种?( )
【单选题】If a variable is declared in a compound statement within a function, the variable( )
A.
is valid in the compound statement only
B.
is valid in the function
C.
is valid in the program
D.
is an illegal variable
【判断题】反倾销税是指在正常关税以外,由进口国海关对倾销产品征收的一种附加税,由实施倾销行为的出口商缴纳。