Ask for help for a chemistry problem, hoping for a solution process!

First of all, because sodium is less electronegative than lead. It can be known that the cation is Na+. Anions are actually complexes. For diamino-lead(-4), there are a total of nine atoms in line with the title. So the chemical formula should be Na4

First of all, this seems to be a physics problem

As shown in the figure, if you use the left eye to see a complete image, you need to use a plane mirror between the PRs, and if you use the right eye to see a complete image, you need a plane mirror between the QS, so you can see the complete image with both the left eye and the right eye closed.

It is not difficult to learn from geometry ps=(a+b) 2,<>

This is a typical balancing problem, to be followed by equilibrium.

The regular calculation is determined by the CO2 of this reaction.

The equilibrium constant, independent of the amount of solids, is re-interested.

The equilibrium of CO2 is calculated using the ideal gas equation.

When the amount of matter, the equilibrium amount of CaCO3 is.

Got it, the specific process is shown in the figure below.

By definition, the carbon dioxide concentration or partial pressure is equal to the equilibrium constant, and the units are converted in SI units.

So only a small fraction of calcium carbonate can be decomposed.

I did it my way

It should be that this hydrocarbon reacts with oxygen almost completely, because the title mentions that "after being absorbed by the NaOH solution, the container almost becomes a vacuum", which shows two problems, one is that the CO2 generated by the reaction is completely absorbed. Second, the hydrocarbons should be completely combusted, and the CO generated is negligible.

Solution: Let the chemical formula of this hydrocarbon be CXHY.

The pressure of the gas in the vessel after the reaction of CXHY+(X+Y4)O2 XCo2+Y 2H2O is half of that before the reaction.

There is an equation: 1+x+y 4=2x (because water is liquid at 20 degrees Celsius, the volume is not included in the gas volume).

Get 4x-y=4

With the relationship between X and Y, it's easy to do. ）

Substituting x=1 and y=0 are inconsistent.

Substituting x=2 and y=4 is in line with the title, which is C2H4, that is, ethylene.

Substituting x=3 and y=8 is also in line with the title, which is c3h8, i.e., propane.

Substituting x = 4 and y = 12, when there are 4 carbon atoms, there can only be 10 hydrogen atoms at most, so it does not fit the topic.

As for x = 5, 6, 7 ......It's also not in line with the topic.,The answer should be c2h4,c3h8 finished If you don't understand, you can hi me.

You can substitute the answer into the question, C2H4 + 3O2 = = 2CO2 + 2H2O, gas pressure ratio = gas volume ratio = stoichiometric ratio, so the ratio of volume after reaction to before reaction is 1 2. It's okay to work backwards. Or hydrocarbon combustion to leave CO2 and water, the original hydrocarbon plus O2 volume is twice the amount of the remaining CO2, you can calculate it yourself.

m(co(nh2)2)=

Nitrogen content of urea:

More 100 million tons need to be produced.

Mass fraction of N in CO(NH2)2 = 28 60

One ton of grain needs to provide tons of nitrogen, 100 million tons of grain needs 100 million tons of nitrogen, and the mass of urea needs 100 million tons.

What 100 million tons of food needs is 100 million tons of nitrogen. In Co(NH2)2, it is solved proportionally according to the relative atomic weight. The atomic weight of nitrogen is 14, that of carbon is 12, that of oxygen is 16, and that of hydrogen is 1

The total molecular formula is 60, and what we need is 100 million tons of nitrogen, so how much urea do we need? Just follow this ratio.

14 60= Then solve for x= and divide by 2

This is the mass of the urea we want to be 100 million tons.

China wants to increase 100 million tons of grain every year, if the production of each ton of grain needs to provide tons of nitrogen, how many atoms are in a urea molecule? If all the nitrogen needed is provided by urea, how many tons of extra tons of urea will China need to produce?

According to the above calculations, how many more ammonia (NH3) plants with an annual output of 200,000 tons need to be built in order to increase the production of urea?

1.With a solution of 38% hydrochloric acid (the density is 500g of 10% dilute hydrochloric acid, how many milliliters of 38% hydrochloric acid solution and water are needed?) (The calculation is accurate.)

Solution: Let 38% hydrochloric acid be x, and the solution is: x=

2.In laboratory water electrolysis tests, the addition of sulfuric acid can enhance the conductivity of water. If the mass fraction of water in 100g of dilute sulfuric acid solution before the experiment is 99%, and after a period of electrolysis, the mass fraction of water in the sulfuric acid solution becomes 98%, how many grams of electrolyzed water is found?

Write down the steps.

Solution: 100 (99%-98%) hydrochloric acid.

Mass of water: [100 (99%-98%) Mass of water: *18 (g)

Do it yourself, and good luck?