The title is123455678 91110213.
The answers are BCA, BCA, BCB, BCB, BCB, BCB.
Title:141516171819 202122 23 24 25.
Answer: DBD, DBD, BCC, BCC, BCC, BCC.
1. The following changes are physical changes ()
A. Wood burns B. Boiler explodes C. Powder explodes D. Candles become shorter when lit.
2.65438+In the 1970s, the scientist who came to the conclusion that air was composed of oxygen and nitrogen through experiments was ().
A. Dalton Mendeleev lavoisier Avo Gadereau
3. The following instrument can't be used as a reaction container is ().
A. measuring cylinder B. test tube C. gas container D. beaker
4. The following four gases by volume, the content in the air from less to more is ().
① Rare gas ② Nitrogen ③ Oxygen ④ Carbon dioxide
A.①②③④ B. ④③②①
C.④①③② D. ③②④①
Some metal crafts have silvery metallic luster, and students think they may be as magnetic as iron. During the discussion, some students suggested that "you can take a magnet to suck it first". As far as the process of "taking a magnet to suck" is concerned, it belongs to () in scientific inquiry.
A. Suppose B. Experiment C. Observe D. Draw a conclusion
6. The following four kinds of bottled gas storage method is correct ()
Smooth face up, smooth face up, frosted face up, frosted face up.
A B C D
7. When measuring liquid, a classmate began to use the overlooking reading of 15mL. After pouring a certain amount of liquid, the overlooking reading was 5mL, so the volume of liquid poured out by the classmate was ().
A. >10ml B. <10ml C. =10ml D. Not sure.
8. The description of the following experimental phenomena is correct ()
A. Sulfur burns in the air, giving off a blue-purple flame and producing a gas with a pungent smell. B. Red phosphorus burns in the air and produces a lot of white smoke. C. The iron wire burns violently in oxygen, and sparks are everywhere.
D, the magnesium strip emits dazzling white light in the air to generate magnesium oxide.
9. Air Quality Daily is a monitoring report made by the environmental monitoring department on the air quality of an area. At present, the main pollutants in the air are inhalable particles, carbon monoxide, sulfur dioxide and nitrogen oxides. Can directly cause air pollution in the following situations is ()
A. Discard waste batteries at will. B. Use clean energy such as solar energy and wind energy.
C. Discard plastic waste at will D. Use coal and oil as main fuels.
10. The following experimental operation statement is correct ()
A, putting a massive solid into an upright test tube; B. Hang the rubber dropper directly above the test tube and drop the liquid into the test tube.
C in order to save medicine, the remaining medicine should be put back into the original bottle immediately after the experiment. D. The waste liquid from the experiment should be directly poured into the sewer.
1 1. The basis for judging whether the iron wire combustion is a chemical change is ().
A. generate a black solid B. emit dazzling light and sparks everywhere.
C. the iron wire is shortened rapidly. Heat is released.
12. A set of instruments should be selected to measure 7.5mL liquid correctly ().
①5mL measuring cylinder ② 10mL measuring cylinder ③20mL measuring cylinder ④ Rubber-tipped dropper.
A.34b.124c.24d. ③ only
13. In order to create a "national environmental protection model city", Nanjing replaced the original trash can with a modular garbage collection box. The picture below shows the Classification Signs of Municipal Domestic Waste issued by the state. The sign that should be posted on the garbage collection box for waste batteries is ().
14 In the following discussion about the concept of oxidation reaction, the correct one is ().
A. oxidation reaction must be a combination reaction B. oxidation reaction is the basic type of chemical reaction
C. oxygen must participate in the oxidation reaction. A reaction can be an oxidation reaction or a combination reaction.
15. "green chemistry" is one of the important directions of chemical science development in the 2 1 century, and its core is to reduce environmental pollution from the source. Do you think "green chemistry" refers to () in chemical production?
A. strictly control waste gas, waste water and waste residue.
B. little or no harmful substances.
C. Don't use any chemicals D. Plant grass and trees in the chemical plant to make it a garden-style factory.
16. Among the following four attributes, one is essentially different from the other three, and this attribute is ().
A. color b state c hardness d flammability
17. Recently, Typhoon Sang Mei swept through Fujian, Guangdong, Zhejiang and other provinces in China, causing huge economic and spiritual losses to the people in the disaster areas. Do you think the main reason for climate deterioration is ().
A. The result of ozone layer destruction B. The result of soil pollution
C. The result of vegetation destruction D. The result of volcanic eruption
18. Among the following substances, the former belongs to mixture and the latter belongs to pure substance ().
A. iodized salt soy sauce b rain ice water * * *
C. distilled water, clean air D. coke vinegar
19. When assembling an oxygen plant in the laboratory, the correct order is ().
A. From top to bottom, from left to right
C. From bottom to top, from left to right D from bottom to top, from right to left
20. At room temperature, the combination of iodine and magnesium is very slow. If you drop a few drops of water, the reaction is quite intense, forming beautiful purple smoke. The function of water here is ().
A. catalysis B. providing heat C. oxidation D. absorbing heat
2 1. In a closed container filled with air, if oxygen is removed by combustion, but other gas impurities are not introduced, the combustible substance that can be used is ().
A. Sulfur B. Charcoal C. Red phosphorus D. Iron
22. The density of a non-toxic gas is about 5/9 of the density of air, and it is extremely difficult to dissolve in water, so the method of collecting gas is ① upward exhaust ② downward exhaust ③ drainage ().
A.①② B.①③ C.②③ D.①②③
23. The process of making oxygen in the laboratory can be roughly divided into the following six main operations:
(1) ignite the alcohol lamp and heat the test tube; (2) extinguish the alcohol lamp; (3) check the air tightness of the device; (4) put the mixture of potassium chlorate and manganese dioxide into the test tube, plug it with a rubber stopper with a catheter and fix it on the iron frame; (5) drain and collect oxygen; and (5) take the catheter out of the water. The correct operation sequence is ()
A.③④①⑤②⑥b .③④①⑤⑥c .④①③⑤②d .④①③⑤⑥②
24. Argon and nitrogen are often mixed and filled into the bulb to make the bulb durable. This is because argon and nitrogen ().
A. it's gas. It has no color. C.it has no smell. It is chemically stable.
25. As can be seen from the following figure, when hydrogen peroxide and manganese dioxide are used to produce oxygen, the curve (t) of the change of the mass of manganese dioxide in the reaction mixture with time is (t indicates the complete reaction) ().
Ah ah ah ah
Oh, oh, oh, oh, oh, oh, oh, oh, oh
A B C D
2. Let me fill in the blanks (this big question is ***7 small questions, each space 1 point)
2 1. Write the symbols of the following elements.
Calcium, chlorine, mercury, iodine, lead, argon, neon, gold, platinum and silver.
22. According to the meaning of the question, write the following reactions in words, and indicate the basic reaction categories in brackets:
(1) Write down two reactions of making oxygen in the laboratory: ()
(2) Carbon monoxide burns in the air to generate carbon dioxide: ()
(3) Mercury is heated in the air to produce a red substance: ()
(4) Fine iron wire burns in oxygen: ()
The following changes: ① phosphorus burns in oxygen; ② Iron burns in oxygen; ③ Aluminum burns in oxygen; ④ Charcoal burns in oxygen; ⑤ Sulfur burns in oxygen; Candles burn in oxygen.
(1) emits white light: (fill in the serial number, the same below); (2) What happens when there is a flame is:
(3) White smoke comes from: (4) Water mist comes from:
24. A classmate did the following experiment on an unknown metal: take a piece of metal, cut it off with a small knife and throw it into the water. The metal floats on the water, reacts violently with the water, rotates rapidly on the water, swims around, hisses at the same time, immediately melts into a shiny silver sphere, and gradually shrinks until it disappears completely. Please analyze the above experimental phenomena and summarize the properties of this metal:
(1) Physical properties: ①, ②, ③, ④. (2) Chemical properties:
25. Weigh the beaker and medicine with a tray balance, and when the balance is reached.
The location of the travel code is shown in the figure (1). If there is a weight of 40 grams on the right side plate of the pallet balance,
Code, beaker weight and drug quality is _ _ _ _ _ _ _ _ _; (2) Due to operational errors, the weighed beaker and medicine were put on the right plate by mistake, and the weight on the left plate of the balance was still 40g, so the actual quality of the weighed beaker and medicine was _ _ _ _ _ _ _ _ _.
26. In order to study the respiration of plants, Xiao Gang designed a device as shown in the figure. please
Discuss the following questions with Xiao Gang.
In the experiment (1), the jar was wrapped in opaque black paper to prevent the jar.
Plants in the room will interfere with the experiment.
(2) After a period of time, you can see the red ink in the thin glass tube (filling
"move left", "move right" or "do not move"). When the black paper outside the jar was removed, it was observed that the jar was wide.
What happens in the mouth bottle is,
The reason is.
27. Mix A and B into clarified limewater, and there is no obvious change in limewater; When black solid butyl hot enough to emit red light is put into the mixed gas, butyl will burn to generate new gas C, and methyl ester will be detected after butyl is extinguished.
The gas has been completely exhausted; Add clear limewater to the mixture of B and C, and the limewater becomes turbid. It is known that gas B accounts for about 4/5 of the air volume, so: (1) These substances are: methyl ethyl propyl butyl.
(2) The literal expression of the reaction between A and D is.
4. I can design (one big question and two small questions, including 28 questions with 4 points and 29 questions with 6 points)
After completing the experiment of heating liquid on page P 17 of the textbook "Activities and Inquiry", Xiaoyu wanted to try to do the experiment of heating solid: he took a test tube, added sucrose solid and heated it on an alcohol lamp. After the experiment, he found that the test tube was broken. Please help him analyze, what are the possible causes of pipe rupture? (Write at least three points)
29. Observe the flame of alcohol lamp. What do you see? See if you can do other experiments. Please design and complete an experiment, and complete the report of inquiry activities (graphics, tables, and text descriptions can be used).