How many short answer questions are there in the third year of junior high school chemistry carbon

1.The molecular structure is different.

2.Oxygen is burned.

3.White phosphorus, yellow phosphorus.

4.Matter, elements.

5.There are wood, bamboo, burned, loose and porous.

1.The molecular structure is different 2Burn it, and there is carbon dioxide generation on it 3

Sulfur 4Metallic elements non-metallic 5Activated carbon is a very fine carbon particle with a large surface area, and there are even finer pores in the carbon particle - capillaries, which have a strong adsorption capacity.

** with a mass ratio of carbon to hydrogen in the product of 3:1: a CO2 with a carbon mass of 12 and 2 water from the equation CH4 + 4Cuo = 4Cu + CO2 + 2H2O is generated with a hydrogen mass of 12 and 2 water with a hydrogen mass of 4, so the hydrocarbon mass ratio is 3:

1 This is the case where only CH4 restores CUO. One to remember!

If the syngas does not have CH4 but only CO and H2, then calculate the mass ratio of carbon to hydrogen in the product: if there is only CO and H2, reduce the sufficient amount of CuO, and the ratio of the number of molecules of CO to H2 in the syngas is 1:3 CO+CuO=Cu+CO2; 3h2+3cuo=3cu+3h2o;The number of CO2 molecules and H2O molecules in the product is 1, the number of H2O molecules is 3, and the mass ratio of carbon to hydrogen is 12. 6=2：

1 Remember 2!

Based on the experimental data, the actual results calculate that the mass ratio of carbon to hydrogen is 9:4, and the actual value is between the two assumptions, so the experimental syngas is neither pure CH4, nor only CO and H2, and B is correct. In addition to CO and H2, there is also unreacted CH4 in the prepared syngas, and CH4 also reduces CUO.

Answer: Original question" Student C proposed that the gas introduced in the experimental procedure will take away part of the water vapor in device E, which will cause errors in the experiment. Do you think this error has any effect on Student B's projections? ”

Original Answer: "No." Since the removal of water vapor will cause the measured CO2 mass to be low, and the mass ratio of carbon to hydrogen in the actual product is greater than 2:1, it has no effect on the estimated results. ”

My explanation is: if the syngas continues to be introduced after the first step is stopped heating, the syngas will inevitably take away the water vapor when it passes through the aqueous solution of sodium hydroxide in the D bottle, and the water vapor will inevitably take away the CO2, but from the calculation, the mass ratio of carbon and hydrogen in the actual measured product is 9:4, and the mass ratio of carbon and hydrogen in the product when the syngas does not have CH4 is 2:1 (regarded as 8:4) The meaning is: there must be CH4 in the actual syngas, and the CO2 taken away by the water vapor is not considered. does not affect B's speculation.

The process is simple, but the words that come out are a bit long, be patient and take a look.

If there is only H2 and Co, that is: CH4 + H2O = Co + 3H2, the ratio of the number of molecules of Co to H2 in the syngas is 1:3;

h2+cuo=cu+h2o;co+cuo=cu+co2, because the ratio of the amount of matter generated by h2 and co is 3:1, then you unify the previous formula with 3, that is, 3h2+3cuo=3cu+3h2o, and the mass ratio of carbon and hydrogen in the product is 12:(3*2)=12:

6=2:1 understand? Note that it is the mass ratio!

If there is only CH4, then the mass ratio of carbon to hydrogen element in CH4+4CuO=CO2+2H2O+4Cu product is 12:(2*2)=12:4=3:1, note that it is the mass ratio of the atom!

The mass of CO2 is measured: 201 5g - 198 2g = 3 3g H20 mass: 896 0g - 292 4g = 3 6g

i.e. the mass of h in the generated h2o is; The mass of C in CO2 is; Mass ratio of carbon element cord to hydrogen element cord in the product: 9:4

9:4 is between 2:1 and 3:1.

It can be inferred that in addition to CO and H2, there may be CH4 in the prepared syngas.

CH4 also restores cuo.

I don't know if I'm clear? Hope you understand!

2. If it's just baico and h2, they'll come to du

The source is: CH4 + H2O = Co + 3H2, the CO and H2 used to reduce CUO are all from this reaction, and after the reaction, they are turned back to CO2 and H2O respectively, according to the conservation of the answer, it can be seen that the number ratio of carbon atoms and hydrogen atoms is extremely the number ratio in the equation: 1:

6. The mass ratio is 2:1

If only CH4 reduces CUO, you don't actually need to think about the equation (CH4+4CUO=4Cu+CO2+2H2O), just use the conservation 'carbon atom and hydrogen atom are all from CH4, where the ratio of hydrocarbon to hydrogen is 1:4, and the mass ratio is 3:1

The actual situation is that the mass of CO2 is now measured: 201 5g--198 2g = 3 3g The mass of H20: 896 0g - 292 4g = 3 6g, and the mass ratio of carbon element cord to hydrogen element cord in the product is:

3·3g×(12/44))：3．6g×(2/18))=9：4

I can't see the diagram and can't explain it for you3

It is still 27 questions in the 2010 high school examination paper in Nanjing.

It is difficult to read the text, so it is best to ask the teacher, because you may not be able to understand it right away.

Carbon is burned in oxygen, and when oxygen is insufficient, carbon is incompletely burned to produce carbon monoxide, and when oxygen is sufficient, carbon is completely burned to produce carbon dioxide Therefore, when carbon is fully burned in oxygen, the product is carbon dioxide, and the chemical formula is: CO2

To sum up, the answer is: CO2

The "carbon" in carbon neutrality refers to carbon dioxide.

"Carbon" means carbon dioxide, and "neutralization" means positive and negative offsets. The carbon dioxide or greenhouse gases emitted are offset by afforestation, energy conservation and emission reduction, etc., which is called "carbon neutrality".

"Carbon" refers to natural resources made of carbon, such as oil, coal, and wood. "Carbon" is consumed a lot, and the culprit of global warming is also produced, "carbon dioxide". With human activities, global warming is also changing (affecting) people's lifestyles, bringing more and more problems.

Relevant social context

Global warming is the consequence of the Earth's climate change caused by human actions. "Carbon" refers to natural resources made of carbon, such as oil, coal, and wood. "Carbon" is consumed a lot, and the culprit of global warming is also produced, "carbon dioxide".

With human activities, global warming is also changing (affecting) people's lifestyles, bringing more and more problems.

In 2002, a 3,250-square-kilometre ice shelf in Antarctica fell off and melted away within 35 days; And according to the latest NASA data, Greenland melts an average of 221 cubic kilometers of ice every year, twice as much as it melted in 1996.

The mass fraction of medium oxygen is 8 11 and CO is 4 7

If CO2 and CO contain the same mass of oxygen in the pure pairing, the mass ratio of CO2 to CO is the inverse ratio of CO2 to the mass fraction of oxygen in CO is 11 14

Reacting with Cuo, there is also Z generation, saying that Shan Ming X is oxidized, except for O2, everything else can be oxidized by reaction with Cuo.

It's common sense.

carbonization dry distillation; carbonization；carbonification

Also known as dry distillation. Thermochemical processing methods for solid fuels. Coal, wood, oil shale, etc. are heated and decomposed into gas (gas), liquid (tar) and solid (coke) products under the isolation of air, and the tar vapor escapes from the coke oven with the gas and can be utilized, and the coke is pushed out from the coke oven.

The thermal decomposition of organic compounds into carbon and other products in the isolation of air, and the dehydration of carbon, hydrogen, and oxygen-containing compounds (such as sugars) into charcoal with a strong absorbent (concentrated sulfuric acid) is also called carbonization. The ratio of hydrogen and oxygen atoms removed during carbonization is 2:1.

It refers to a pyrolysis technology of biomass under anoxic or oxygen-poor conditions for the purpose of preparing the corresponding carbon material, and its process is synchronized with the decomposition of biomass, wood fiber and lignin

Carbonization is the same as carbonization.

The dehydration of concentrated sulfuric acid is also called carbonization.

Carbon is an element and is elemental.

Charcoal is a mixture that is mainly made up of carbon.

Summary. Hello, a certain amount of carbon is burned, and when the oxygen concentration is low, the combustion product is carbon monoxide. When the oxygen concentration is high, the product produced by combustion is carbon dioxide. When the oxygen concentration is somewhere in between, the resulting product is a mixture of carbon monoxide and carbon dioxide.

Twelve grams of carbon are burned in a certain mass of oxygen to obtain different products. Relationship between carbon and oxygen.

Wait a minute. Hello sedan car, a certain amount of carbon burning, when the oxygen concentration is low, the combustion product is carbon monoxide. When the oxygen concentration is high, the product produced by combustion is carbon dioxide.

When the oxygen concentration is between the two, the resulting product is a Zhengxiang mixture of carbon monooxoxide and carbon dioxide.