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问题 选择题

能用H++OH-=H2O表示的化学方程式是（　　）

A．氢氧化钠溶液与醋酸反应

B．氢氧化铁与硫酸反应

C．氢氧化钡与硫酸反应

D．硫酸氢钠与氢氧化钠溶液反应

答案

A．醋酸为弱电解质，应写成化学式，不能用H++OH-=H2O表示，故A错误；

B．氢氧化铁难溶于水，应写成化学式，不能用H++OH-=H2O表示，故B错误；

C．氢氧化钡与硫酸反应生成硫酸钡沉淀和水，不仅仅发生H++OH-=H2O，故C错误；

D．硫酸氢钠与氢氧化钠溶液反应的离子方程式为H++OH-=H2O，故D正确．

故选D．

单项选择题

癔症性躯体障碍主要表现为

A．运动障碍与感觉障碍
B．遗忘
C．意识障碍
D．双重人格
E．癔症性神游
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填空题

根据上下文或括号里的汉语提示，在下面短文的空白处写出正确的单词或词组，使短文意思完整，

语句连贯。

     About more than a hundred years ago, an American produced a game. He called it 1.              (室内的)

tennis. The Americans were not interested in it 2.              (起初), but he sent it to his London friends and

it became very 3.              (流行的) in Britain. The game was then played across dining-room tables,

or 4.              (在地板上) with the net strung (用绳缚) 5.              (在……之间) two chairs. The

balls 6.             (由…制成) cork(软木)or rubber. The bats were made of wood. 7.              (几年之后) a

hollow (空心的) ball like the one we use today was invented. The game then 8.              (快速地) spread

all over the world. An Englishman once made a bat covered with rubber. He first sold the game in England

and called it "Ping-pong". "Ping" was the 9.              (声音) of the bat when it hit the ball, and "pang" was

the 10.              (第二) sound of the ball when it hit the table.

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