(10龙岩市18). 金属氢化物如氢化钙(CaH2)、氢化钠(NaH)是一种重要

题型:计算题

问题:

(10龙岩市18). 金属氢化物如氢化钙(CaH2)、氢化钠(NaH)是一种重要的制氢剂,与水接触时,分别发生如下反应

CaH2+2H2O=Ca(OH)2+2H2↑    NaH+H2O=NaOH+H2

(1)若某化学反应需要消耗10g氢气,需要消耗多少克NaH?

(2)登山运动员登山时也需通过金属氢化物与水反应获得氢气以提供必须的能量。小红认为,若用CaH2替代NaH,有利于登山运动员减轻包袱负担。为什么?

考点:合成有机高分子材料
题型:计算题

近十年来,我国重工业发展迅速,重工业增长值长期占工业增长值的60%以上,尤其是钢铁、汽车、化工等重化工业得到了快速发展。我国能源利用率较低,单位GDP能源消耗远远高于世界平均水平。据此回答问题。

小题1:目前,我国重化工业加速发展所带来的问题主要有

A.交通运输压力加大

B.水土流失、荒漠化严重

C.资源和能源的消耗量大

D.耕地面积减小,劳动力短缺小题2:针对目前我国单位GDP能耗、物耗远远高于世界平均水平现状,需要采取的措施有

A.加强技术和生产工艺上的革新,提高能源和资源的利用率

B.对紧缺的矿产资源停止开发,加大对储量丰富的资源的开发力度

C.严格限制高能耗工业的发展

D.加大重污染、高能耗企业的劳动力投入

题型:计算题

An eight-year-old child heard her parents talking about her little brother. All she knew was that he was very sick and they had no money left. When she heard her daddy say to her (1) mother," (2) a miracle can save him now", the little girl went to her bedroom and took out her piggy bank. She (3) all the change out on the floor and counted it carefully. Then she (4) her way six blocks to the drugstore.

"And what do you want" asked the shopkeeper. "It’s (5) my little brother," the girl answered back. "He’s really, really sick and I want to buy a (6) . His name is Andrew and he has something (7) growing inside his head and my daddy says only a miracle can save him. " "We don’t (8) miracles here, child. I’m sorry." the chemist said, smiling (9) at the little girl.

In the shop was a (10) customer. He stooped down and asked the little girl, "What kind of miracle does your brother (11) " "I don’t know," she replied. "He’s really sick and mommy says he needs (12) . But my daddy can’t pay for it, so I have brought my (13) .""How much do you have" asked the man. "One dollar and eleven cents, (14) I can try and get some more," she answered quietly. "Well, what a coincidence," smiled the man. "A dollar and eleven cents—the (15) price of a miracle for little brothers. (16) me to where you live. I want to see your brother and (17) your parents. "

That well-dressed man was Dr Carlton Armp, a doctor. The operation was completed without any (18) and it wasn’t long before Andrew was (19) again. The little girl was happy. She knew exactly how much the miracle cost—one dollar and eleven cents—also the (20) of a little child.

6().

A.hope

B.doctor

C.favor

D.miracle

题型:计算题

与乳牙特点无关的是()

A.乳牙的根干比恒牙长

B.牙冠相对短小

C.颈嵴明显

D.乳牙牙冠颜色比恒牙白

E.乳切牙根尖向唇侧弯曲

题型:计算题

46岁妇女,患慢性肾炎多年,半年前曾因早孕行人工流产术。现要求避孕指导。本例选择最恰当的避孕措施应是()

A.安全期避孕

B.口服短效避孕药

C.皮下埋植避孕

D.阴茎套避孕

E.行输卵管结扎术绝育

题型:计算题

种肥

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