【单选题】听力原文: Tennis was one of the original sports played at the modern Olympic Games which were held in Athens, Greece in 1896, and it lasted until the 1924 Games in Paris. Later tennis was dropped out from...
A.
Because the equipment was unstable.
B.
Because the roles of the game were altered.
C.
Because the players of tennis were disliked.
D.
Because the date was different from the Wimbledon.
【单选题】参与构成血-脑屏障的胶质细胞主要是 ______ 。
【单选题】which of the following sports is not included in Summer Olympic Games ( ) .
【单选题】在0.1mol/L醋酸溶液中,下列说法不正确的是( )。
A.
加入少量氢氧化钠溶液,醋酸的电离平衡向右移动
C.
加入浓醋酸,由于增加反应物的浓度,使醋酸的电离平衡向右移动,电离度增加
【单选题】向20 mL氢氧化钠溶液中逐滴加入0. 2 mol/L醋酸溶液,滴定曲线如下图所示下列说法不正确的是 ( )
A.
该氢氧化钠溶液的物质的量浓度为0.1 mol/L .
B.
在b点,c (Na + )=c(CH 3 COO - )
C.
在d点,溶液中所有离子浓度由大到小的顺序为 c (CH 3 COO - )>c (Na + )>c (H + )>c (OH - )
D.
氢氧化钠溶液与醋酸溶液恰好完全反应的点位于曲线b、d间的某点
【简答题】简要分析 计算机网络采用层次结构模型有什么好处。
【单选题】保时捷车辆上制动盘安装时横向跳动的极限值为 ?
【简答题】Read the text on the Olympic s and answer the following questions. The Olympic Gam The Olympic s are a major international which includes both summer and winter sports. The modern Intern...
【单选题】下列说法正确的是( )
A.
常温下醋酸分子不可能存在于pH>7的碱性溶液中
B.
常温下向氯化铵溶液中加入少量氨水使溶液的pH=7,则混合溶液中c(N )>c(Cl - )
C.
0.1 mol·L -1 的氯化铵溶液与0.05 mol·L -1 的氢氧化钠溶液等体积混合后溶液中离子浓度的大小关系是:c(Cl - )>c(N )>c(Na + )>c(OH - )>c(H + )
D.
0.1 mol·L -1 硫化钠溶液中离子浓度的关系:c(Na + )=c(S 2- )+c(HS - )+c(H 2 S)