下列反应中属于化合反应的是( ) A.煅烧石灰石:CaCO3=CaO+CO2↑

题型:选择题

问题:

下列反应中属于化合反应的是(  )

A.煅烧石灰石:CaCO3=CaO+CO2

B.用稀盐酸除铁锈:Fe2O3+6HCl=2FeCl3+3H2O

C.实验室制取二氧化碳:CaCO3+2HCl=CaCl2+H2O+CO2

D.镁用做燃烧弹:2Mg+O2=2MgO

考点:化合反应
题型:选择题

When I was a child, there was a fair (集市) every autumn in my town. Lots of people from other towns        to sell and buy things. During the fair, my        became the busiest person of the family. All of her relatives (亲戚) would come and live        her house and have meals there. Grandma was happy to        them.

Years later, there was no fair any more. Grandma’s relatives didn’t come every        like before. Grandma often sat in her room for hours,        saying a word. She didn’t look       .

This year our town has decided to reopen (重开) the fair. When Grandma        this, smiles come back on her face. She looks much       . She tells me that her nieces (侄女) are coming. “They are        here for one week,” she says happily.

I suddenly know that Grandma doesn’t want others to look after her. She wants to be useful and helpful.

小题1:

A.heard

B.talked

C.planned

D.came小题2:

A.mother

B.grandma

C.father

D.grandpa小题3:

A.of

B.to

C.in

D.by小题4:

A.turn on

B.come over

C.put on

D.look after小题5:

A.autumn

B.spring

C.winter

D.summer小题6:

A.about

B.without

C.like

D.for小题7:

A.happy

B.sad

C.healthy

D.weak小题8:

A.knows

B.says

C.writes

D.thinks小题9:

A.freer

B.more

C.younger

D.less小题10:

A.working

B.driving

C.leaving

D.staying

题型:选择题

比232多189的数是(    ),比320少153的数是(    )。

题型:选择题

5千克大米14元钱,买5.4千克同样的大米应付______元钱.

题型:选择题

某学生在课外活动中用一定量的二价金属R和稀硫酸反应来制取氢气,所做5次实验结果记录如下表(假设每次实验所产生的氢气全部被收集,体积在同温同压时测定).

实验编号R的质量/g稀硫酸的体积/mL生成H2的体积/L
1.550.01.47
2.050.01.96
2.250.02.16
2.550.02.16
3.050.02.16
根据上述实验结果进行分析、计算,并回答下列问题:

(1)上述实验中,金属一定过量的组的编号是______,稀硫酸一定过量的组的编号是______.

(2)若在当时实验条件下,氢气的密度为0.085g/L,则反应所用金属R的相对原子质量为______.

(3)若所使用的稀硫酸的密度为1.12g/cm3,则反应所用的硫酸溶液中溶质的质量分数为______.

题型:选择题

急性早幼粒细胞白血病是通过

A.血管内皮广泛受损激活Ⅻ因子导致DIC
B.组织严重破坏,造成组织因子入血导致DIC
C.红细胞大量破坏导致DIC
D.白细胞大量破坏导致DIC
E.其他促凝物质入血导致DIC

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