根据所给算式请直接写出得数.3×20=6011×8=884×30=12060×2

题型:解答题

问题:

根据所给算式请直接写出得数.
3×20=60
11×8=884×30=12060×20=11×16=
11×160=4×60=9×20=11×24=11×240=
4×120=12×20=11×32=11×320=4×240=
考点:和差积商的变化规律
题型:解答题

某同学对第四周期过渡元素产生浓厚的兴趣.想探究是否只有MnO2能催化KClO3受热分解?CuO、Fe2O3、Cr2O3等对氯酸钾的受热分解有没有催化作用?若有催化作用,效率怎样?请你与他一起进行实验探究:

I.课题名称:______.

Ⅱ.实验仪器:略

实验试剂:二氧化锰、氧化铁、氧化铜、氧化铬和氯酸钾

Ⅲ.实验步骤:略

Ⅳ.实验数据:

实验

编号

KClO3

(g)

氧化物产生气体(mL)

(已折算为标况)

耗时(s)
化学式质量(g)回收
10.6---10480
20.6MnO20.2090%67.236.5
30.6CuO0.2090%67.279.5
40.6Fe2O30.2090%67.234.7
50.6Cr2O30.20异常67.2188.3
V.实验讨论:

(1)请用编号3的实验数据求得KClO3的分解率:为______%(保留一位小数).

(2)在用Cr2O3做实验时,有刺激性气味的气体产生,同时绿色的混合物变成橘黄色(K2Cr2O7).该刺激性气体可能是______(填化学式),用______检验.(填序号)

A、湿润的蓝色石蕊试纸           B、湿润的碘化钾淀粉试纸

C、湿润的PH试纸                D、湿润的红色石蕊试纸

Ⅵ.实验结论:______.

题型:解答题

第II卷(共21分)

第四部分 写作(共2节,满分21分)

第一节:单词拼写 (共12小题;每小题0.5分,满分6分)

73. He looks very young, but a___________, he is in his fifties.

74.In that big fire all their houses were completely d___________, so they had to build new ones.

75. Please use the words to make a sentence a___________to the situation.

76. More and more people realize the importance of wildlife p___________.

77. Mike works far away from home and he is always c______about the health of his aging parents.

78. The new model sells well because it is of good q___________ and the price is low.

79. After years of hard work, she s___________ in winning a gold medal in 2008 Beijing Olympics.

80. Can you help me? I have difficulty in s___________ this problem, which upsets me very much.

81. You should take a positive a___________toward life, so you will feel your life full of laughter.

82. We all think highly of the girl who was a___________ into Beijing University last summer.

83. He is a r___________ man, so you can turn to him for help.

84. I believed that nobody could c___________ against him for this position.

题型:解答题

你能写出加横线字在词语中的意思吗?  

思索                                            手不                       

帷幄                                            风声鹤                       

题型:解答题

青木さんも以前はよく顔をみせていたが、最近は___しか来ない。

A.ぜんぜん 

B.めったに

C.たまに 

D.ほとんど

题型:解答题

翻车机具有哪些优点与缺点?

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