做完“铁在氧气里燃烧”的实验后,小名同学有两个疑惑不解的问题,于是他进行了以下探

题型:问答题

问题:

做完“铁在氧气里燃烧”的实验后,小名同学有两个疑惑不解的问题,于是他进行了以下探究活动.

问题1:铁燃烧时溅落下来的黑色物质中还有没有铁呢?

查阅资料1:

(1)自然界中铁的氧化物主要是Fe3O4和Fe2O3两种(FeO极易被氧化为Fe2O3);

(2)铁的氧化物均能溶于酸的溶液.

实验探究:

将冷却后的黑色物质碾碎,装入试管,加入______溶液,观察到的现象是______,说明铁燃烧时溅落下来的黑色物质中还含有铁.

问题2:铁燃烧的产物为什么不是Fe2O3呢?

查阅资料2:

(1)Fe3O4和Fe2O3的分解温度、铁的熔点见表:

Fe3O4Fe2O3
分解温度/℃15381400-
熔点/℃--1535
(2)Fe2O3高温时分解成Fe3O4

理论探讨;

经实验测定铁在氧气里燃烧的产物是Fe3O4,结合表中数据,可推知铁在氧气里燃烧时产生的高温应在______之间,在此温度范围内______已分解.

拓展延伸:

(1)实验中为了防止集气瓶炸裂,必须______;

(2)有些食品包装盒的透明盖内放有黑色的FeO粉末,若粉末的颜色______,就说明包装盒破损进气,这样售货员就能及时发现并处理.

考点:物质的鉴别物质的推断
题型:问答题

大庆号称油城、阜新号称煤城、伊春号称林都,这些城市今天面临的现状却是石油逐年减产、煤矿采挖殆尽、森林采伐过度。造成这种情况的主要原因是[ ]

A.其它地区资源短缺              

B.人口的急剧增加

C.资源的利用率低                

D.对资源的过度开发

题型:问答题

Your genetic makeup plays a big part in determining your size and weight. If both your parents are tall, there is a good chance you’ll be tall. But if your parents are smaller than average, you may want to rethink that professional basketball career!

The same goes for your body type. Have you ever heard someone say a person is “big boned?” It’s a way of saying the person has a large frame, or skeleton(骨骼). Big bones usually weigh more than small bones. That’s why it’s possible for two kids with the same height, but different weight, to both the right weight.

Being overweight can run in someone’s family, but it may not be because of their genes. Poor eating and exercise habits also run in families and these may be the reasons the members of a family are overweight. And even though some kids gain weight more easily than others, when they eat right and exercise, most kids can have a healthy weight that’s right for them. It’s true- the way you live can change the way you look.

How much your weight is a balance between the calories you eat and the calories you use. If you eat more calories than your body needs to use, you will gain too much weight. If you spend you free time watching TV, your body won’t use as many calories as it would if you played basketball, skated, or went for a walk. But if you eat more and exercise less, you may become overweight. On the other hand, if you eat less and exercise more, you may lose weight.

小题1: Which one can be used as the best title of this passage?

A.What Makes Me the Weight I Have?

B.How Can I Lose More Weight?

C.What Makes Me the Height I Have?

D.Is the Way You Live Important?小题2:_______ might be the most important in determining your size and weight.

A.Your father and mother

B.Your genetic structure

C.Your diet and habit

D.Doing exercise in the morning小题3:If two kids are of the same height _______.

A.they must have large frames.

B.they must be of the same size

C.they must be of the same weight

D.their weight might be different小题4:Which one of the following is TRUE according to the third paragraph?

A.Eating right and exercise normally can keep you healthy.

B.The members of a rich family must be overweight.

C.The way you live has nothing to do with the way you look.

D.the members of a poor family can’t be overweight.小题5: ______ can help you to get your weight right.

A.Watching TV in your spare time.

B.Eating more and doing less exercise

C.Eating less and doing more exercises

D.Sleeping more in your spare time

题型:问答题

目胞色黑晦暗,多属()。

A.心火

B.肺火

C.脾虚

D.肝火

E.肾虚

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