按下列要求书写的化学方程式正确的是( ) A.铁在氧气中燃烧:4Fe+3O2点燃

题型:选择题

问题:

按下列要求书写的化学方程式正确的是(  )

A.铁在氧气中燃烧:4Fe+3O2

 点燃 
.
 
2Fe2O3

B.澄清石灰水和盐酸发生中和反应:CaO+2HCl═CaCl2+H2O

C.用碳酸氢钠治疗过多胃酸:NaHCO3+HCl═NaCl+H2O+CO2

D.检验混合气体中是否含有二氧化碳:CO2+2NaOH═Na2CO3+H2O

考点:化学反应方程式的书写文字表达式酸的性质酸的用途碱的用途
题型:选择题

What does little birdie say,

In her nest at peep(初现)of day?

Let me fly, says little birdie,

Mother, let me fly away,

Birdie, rest a little longer,

Till the little wings are stronger.

So she rests a little longer,

Then she flies away.

What does little baby say,

In her bed at peep of day?

Baby says, like little birdie,

Let me rise and fly away.

Baby, sleep a little longer,

Till the little limbs(四肢) are stronger.

If she sleeps a little longer,

Baby too shall fly away.

小题1: In the poem, which words rhyme with "say"?

A.longer, stronger

B.say, day

C.day, away

D.A, B and C小题2:In the poem, where does the bird rest?

A.In her bed.

B.In her nest

C.At peep of the day.

D.In the sky.小题3: How do you understand the last sentence If she sleeps a little longer, Baby too shall fly away?

A.If the baby sleeps for a long time, she can fly.

B.The baby is too lazy, so she wants to sleep longer.

C.The baby has a special ability to fly like a bird after she sleeps longer.

D.You should get enough power and abilities before you do something.

题型:选择题

We go to school __________ Monday __________ Friday.[ ]

A. on; and      

B. on; on

C. in; in          

D. from; to

题型:选择题

在心理层面上,中国人对自身的确认,有“身体发肤,受之父母,不敢毁伤,孝之始也”的观念,若生命始于一个细胞的“克隆”,可能使人们难以接受,并且失去对生命的神圣感。在技术层面上,有性繁殖是自然进化的结果,它所包含的确定性和不确定性,基本上能够保证人类适应自然的生存条件;但是,“克隆人”在进化上的不确定性,是否有利于他们适应自然而生存,人们还难以预料。

这段文字的主旨概括最确切的是()。

A.“克隆”技术面临的难关

B.中国人的生命观念与“克隆人”技术的冲突

C.有性繁殖与无性繁殖的主要区别

D.中国人难以接受“克隆人”技术的原因

题型:选择题
下列装置中不是直接利用太阳能的是(  )

A.电冰箱

B.太阳灶

C.光电池

D.太阳能热水器

题型:选择题

加强足三阴、足三阳经脉与心脏联系的是( )

A.别络

B.经别

C.阴维脉

D.阳维脉

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