【单选题】在0.1mol/LNa 2 S的溶液中,下列关系不正确的是( )
A.
[H 2 S]+[HS - ]+[S 2- ]=0.1 mol/L
B.
[Na + ]+[H + ]=2[S 2- ]+[HS - ]+[OH - ]
C.
[OH - ]=[H + ]+[HS - ]+2[H 2 S]
D.
2[Na + ]=[S 2- ]+[HS - ]+[H 2 S]
【单选题】The old oak tree in the churchyard for 300 years before the church .
B.
would stand; was built
【单选题】I stopped the car ____ a short break as I was feeling tired.
【单选题】I stopped the car ____ a short break as I was feeling tired.
【简答题】动物体 内含有 维生素( ) , 植物 中 不含维生素 ( ) ,只含有 ( ) 。
【判断题】所有植物性饲料中不含有维生素A,而在动物体内含有维生A。
【判断题】两个人从监牢的铁窗望出去。一个看到泥上,一个却看到了星星。该名言是指环境不同对人的内心产生影响。
【单选题】下列不属于微生物转化特点的是 ()
A.
以具有活性中心和特殊空间结构的蛋白质酶作为催化剂
【单选题】(2013·山东高考)I stopped the car ________ a short break as I was feeling tired.
【单选题】100ml0.02mol/LNa 2 SO 4 , 溶液的渗透浓度为( )