Two junior high school chemistry fill in the blank questions, two junior high school chemistry fill

1 Relatively active oxidation oxidation.

2 Differences: Iron burns very violently; Iron rusts more slowly. In the process of iron combustion, part of the iron is +2 valence, part of the iron is +3 valence, and the combustion product is Fe3O4; In the process of iron rusting, the iron shows +3 valence, and the main chemical composition of the resulting rust is Fe2O3 H2O.

All belong to oxidation reactions.

1 Active Reduction Oxidation.

2 Differences: Combustion produces ferric oxide, rust is iron oxide; The former is more violent.

Similarities: both are redox reactions; will release heat.

1.Active oxidation oxidation.

2.The reaction conditions are different, and the products are different.

All are oxidation reactions.

Active oxidation oxidation.

Differences: Combustion produces ferric tetroxide, rust is iron oxide, and the reaction rate is also different, the former reflects.

The phenomenon is full of sparks, the latter reflecting the production of reddish-brown rust.

Similarities: both are redox reactions; will release heat.

1 Answer: Active oxidation (combustion) oxidation (reduction).

2 Analysis: Combustion produces black ferric oxide, and the resulting rust is red iron oxide (ferric oxide), and the color is different, the substance is also different, and the valency of the two iron elements is also different.

Answer: Different colors, different substances, and different valencies of iron. The two substances have the same type of element!

Active oxidation oxidation.

Differences: Combustion produces ferric oxide, rust is iron oxide; The former is more violent.

Similarities: both are redox reactions; will release heat.

1 (lively) (flammability) (reduction).

2 (The conditions of the reaction are different, the products of the reaction are different, and the intensity of the reaction is different) (all are oxidation reactions).

Oxygen is a chemically (active) gas, oxygen has (oxidizing) properties and is a common (oxidizing) agent.

The difference between the combustion of thin iron wire in oxygen and the rusting in air is (the products produced are different), and the similarity is (both are oxidation reactions).

Relatively active Oxidation Oxidation The difference is that when burning, the oxidation reaction is violent, and rust is a slow oxidation reaction, and the similarity is that oxygen participates in the reaction.

Active oxidation oxidant burns violently in oxygen, oxidizes violently, rusts in the air, oxidizes slowly, and is an oxidation reaction.

Active oxidation oxidation. The reaction rate is different, the products are different, and the phenomena are different. The similarity is that they are both oxidation reactions.

Active oxidation oxidation.

2.The products are different, and they are all oxidation reactions.

The first picture. 71% of the earth's surface is covered by water, and the available freshwater resources are very limited.

Adsorption, precipitation, filtration, and distillation.

Hydrogen oxygen 2 hydrogen atoms 1 oxygen atom.

The second picture. The interval gas interval is small.

Molecule atoms.

Chemical change Chemical change Chemical change.

2,1, About 71% of the earth's surface is covered by water Fresh water accounts for only the world's water storage, and only the available water conserves water and prevents water pollution.

2. Precipitation, filtration, adsorption, distillation.

3 Hydrogen Element Oxygen Element 2 Hydrogen Atoms 1 Oxygen Atom.

1 (1) Gap The gap is larger and the gap is smaller.

2) Molecules and atoms.

3) Physical change Chemical change Chemical change.

Solution: Anhydrous copper sulfate mass fraction: 160

Cholelum cuso4 mass split charter shipment: 250

The amount of dry beams required for anhydrous copper sulfate:

MCUSO4=400 4-beam = 16

The quality of the bile alum is required:

mcuso4·5h2o=16×250/160=25o∩_∩o

The first question is to argue that Dan will be the second question, we haven't learned the simple banquet in the third year of junior high school, and the quality of anhydrous copper sulfate is x400g 4 =xx=160g (I'm not good at math, it should be right, carry the disturbance,)

When the amount of hydrated lime is mg, the solution is acidic, and the solute in the solution is the newly formed CAC12 and HC1 that does not fully participate in the reaction. From the chemical equation of the reaction Ca(OH)2 2HC1 CAC12 2H2O and NaOH HC1 NAC1 H2O, it is known that the mass of NaOH is required to neutralize hydrochloric acid of the same mass, that is, NG NaOH cannot completely neutralize the same amount of hydrochloric acid, and the remaining hydrochloric acid in the solution, so its pH 7.

(1) In 2005, a serious water pollution incident occurred in Harbin, and the relevant part used a large amount of activated carbon to evolve water, which is the adsorption of activated carbon.

2) In order to prolong the shelf life of food, some food bags contain a packet of "double absorbent" (the main ingredient is active iron powder), where the "double absorber" absorbs substances such as water and oxygen

1. Adsorption; 2. Oxygen and moisture.

(1) Adsorption.

2) Oxygen and moisture.

a: Potassium permanganate.

B: Oxygen. c: Manganese dioxide.

d: Potassium manganate.

E: Carbon F: Carbon dioxide.

Heating some black solid powder A produces a colorless gas B, which simultaneously produces one black solid C and another solid D, which is often used as a catalyst for heating potassium chlorate to oxygen. (Note that this should be a full stop, and the other black solid E mentioned below has nothing to do with the previous one, so you should pay attention to the review in the future!) Another black solid E burns in a colorless gas B

There must be no carbon in potassium permanganate heating, and it doesn't say that there is carbon (e) above, are you mistaken?

a: Potassium permanganate.

B: Oxygen. c: Manganese dioxide.

d: Potassium manganate.

E: Carbon F: Carbon dioxide.

The black solid E is another substance that is not a product of the decomposition of potassium permanganate during heating.

The title does not say that E (carbon) is obtained by heating A (potassium permanganate). Just another phrase: "Another black solid e".

a：kmno4 b：o2 c：mno2 d：k2mno4 e：c f：co2

Carbon is added to the title and has nothing to do with potassium permanganate.

Heating some black solid powder A produces a colorless gas B, and at the same time produces a black solid C and another solid D", which does not say that there is carbon.

Actually, what I don't understand is that potassium permanganate is not purple-black.

You didn't understand the question: a pyrolysis into b + c + d, *another * black solid e, e + b = f, understand? ("Another solid D" and "another black solid E" are not the same thing).

Classmate, you can see the topic clearly, the pyrolysis of solid powder A does not produce solid E

Dear, there is no E in the substance formed by the decomposition of a.

The meaning of the title is another black solid, which should have nothing to do with the black solid produced by the decomposition of potassium permanganate.

Your teacher is right that E is charcoal, which is judged by the fact that "another black solid E burns in a colorless gas B, producing a gas f that makes the clarified lime water turbid, and the green plants can absorb the gas F through photosynthesis and convert it into a colorless gas B". Among them, the colorless gas B is oxygen, and the gas F that can make the clarified lime water turbid is carbon dioxide, so E should be carbon.

E is not produced by heating A, A produces only three substances: a colorless gas B, a black solid C, and another solid D. You have a problem reviewing the question.

The solid E mentioned above is not produced by the decomposition of potassium permanganate, and the topic is wrong.