某温度时,在2L容器中三种物质的物质的量随时间的变化曲线如下图所示。 由图中数据

题型:不定项选择题

问题:

某温度时,在2L容器中三种物质的物质的量随时间的变化曲线如下图所示。 由图中数据分析,该反应的化学方程式和反应开始至2min末Z的平均反应速率分别为

[ ]

A. 3X+Y2Z; 0.05mol·L-1·min-1

B. 2X+Y2Z; 0.1mol·L-1·min-1

C. X+2Y ==Z;0.1mol·L-1·min-1

D. X+3Y==2Z;0.05mol·L-1·min-1

考点:化学反应速率的计算
题型:不定项选择题

某果农承包的果园中共可种植160棵桃树或杏树.当进入结果期后,一棵桃树每年可结果30kg,一棵杏树每年可结果25kg.按照现在的市场定价,每千克桃子和杏子分别是l.5元和l元.考虑到销路,果农计划两种果树都种植.若果农每年的收入不少于6000元,至少应种植多少棵桃树?

题型:不定项选择题
根据短文内容,从短文后的选项中选出能填入空白处得最佳选项。选项中有两项为多余选项。(每题1分,共5分)
 小题1:   One of the best things you possibly do is start your own club. It’s great fun especially if you are the sort of person who feels there’s never anything to do during the school holidays.
The first thing you  need to come up with is an idea for your club.  小题2:___ Pets, clothes,  pop music or dancing groups, sports, masking things… The lost is endless.
Next you need some friends to be in your club with you.小题3:  __ All you need is three or four other people who are interested in the same thing as you.
 小题4:  __ You should all sit down somewhere together with lots of pieces of paper and write down every name you can think up. That’ll keep you busy for ages.
At your first meeting you should make up a rule book. And the first rule should be no grown-ups or little/big brothers or sisters! The best clubs are always secret!
Now you have just about everything you need, except membership cards. These are very important and again you can spend a lot of time making them. 小题5:  . Why not leave some space for a photo of yourself? That will make the membership card really look like it.
So there you are, get clubbing! Once you get started you’ll think of loads of more interesting things to do!
A.That’s easy.
B.Enjoy your own club!
C.Invite a designer to join you.
D.What are you interested in?
E. Some vacation is just around the corner.
F. Then you need to pick a name for your club.
G. Use a bright thick pen to make a special design.
 
题型:不定项选择题

在人的整个生命周期中,被动发展阶段的年龄约为()。

A.0~3岁

B.3~12岁

C.12岁至成年

D.成年以后

E.以上均不正确

题型:不定项选择题

什么鱼爱吃珊瑚?

题型:不定项选择题

无眠卷材防水层所选用的基层处理剂、接缝胶粘剂、密封材料等配套材料应与铺贴的卷材材性()

A.不相容

B.使用现有材料

C.相容

D.由甲方规定

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