【单选题】相同温度下,体积均为0.5 L的两个恒容密闭容器中发生可逆反应: 2XY 2 (g) + Y 2 (g) 2XY 3 (g) △ H =- Q kJ·mol - 1 ( Q >0) 实验测得反应在起始、达到平衡时的有关数据如下表所示: 容器 编号 起始时各物质物质的量/mol 达平衡时体系能量的变化 XY 2 Y 2 XY 3 ① 2 1 0 放热 0.25 Q kJ ② 1.2 0.6 0....
B.
达到平衡时,两个容器中Y 2 的物质的量浓度均为1.5 mol·L - 1
C.
容器②中反应达到平衡时放出的热量为0.15 Q kJ
D.
若容器①的其他条件不变,恒压下通入稀有气体,则达到平衡时放出的热量小于0.25 Q kJ
【简答题】The newborn was 34 weeks' gestation. The birth weight is 2800g.
the fetal heart is slow, the fetal movement is reduced, Ihe whole body
color is blue at the time of birth.The tension of the four limb...
【简答题】探究函数f(x)=x+ 4 x x∈(0,+∞)的最小值,并确定相应的x的值,列表如下,请观察表中y值随x值变化的特点,完成下列问题: x … 0.5 1 1.5 1.7 1.9 2 2.1 2.2 2.3 3 4 5 7 … y … 8.5 5 4.17 4.05 4.005 4 4.005 4.102 4.24 4.3 5 5.8 7.57 … (1)若当x>0时,函数f(x)=x+ 4 x ...
【单选题】设N A 代表阿伏加德罗常数的数值,下列说法中正确的是( )
A.
1.8 g重水(D 2 O)中含有的质子数和电子数均为1.0N A
B.
0℃、1个标准大气压下,22.4L NO 和22.4L O 2 混合后所得气体中分子总数为1.5N A
C.
含4mol Si-O键的二氧化硅晶体中,氧原子数为2N A
D.
将11.2 L Cl 2 通入足量的石灰乳中制备漂白粉,转移的电子数为0.5N A
【简答题】The web allows for color, graphics, animation, and sound, all of which make the e-commerce a more entertaining and potentially informative experience.
【单选题】连续中断行车6h以上24h一下,属于以下什么类型事件?
【多选题】Which of the following are the features of Chinese food?
A.
Color, aroma and taste are significant.
B.
Sweet in the south, salty in the north, sour in the west and spicy in the east.
C.
Time and temperature play an important role in cooking.
D.
Taste mainly depends on the seasonings.
E.
All the meat are cut into large pieces.