Solve a chemistry calculation problem in junior high school!

3co2...This conservation of atoms can be seen by looking at it.

3co+fe2o3*****2fe+3co28000*(1-19%) x

So 160 (8000*(1-19%))=112 x, and the solution is x=4536

Because the content requirement is 96%.4536 divided by 96% gives 4725

The first one is filled with 3 CO2;

The second one is 8000*, and the result unit is kilograms.

Fill in the blank with 3CO2 (i.e. 3 CO2).

8000kg of ore contains 8000kg of ferric oxide * (1-19) = 6480kg, the amount of ferric oxide is 56 * 2 + 16 * 3 = 160, and the amount of two elemental iron is 56 * 2 = 116, so the elemental iron (6480 * 112) 160 = 4536kg, so the mass of pig iron containing 96 is 4536kg 96% = 4725kg

1. 3co2

In addition to 2 Fe on the left, there are 3 C's and 3 O'sSo here's the answer.

This is the chemical equation for the reduction of iron oxide by carbon monoxide. 2 iron loses 3*2 electrons from positive 3 valence to 0 valence, and 3 carbon gives 2*3 electrons from positive 2 valence to positive 4 valence. This one uses the conservation of electrons.

2. 8000*(1-19%)=6480 kgn(fe2o3)=6480/160= molfe2o3 + 3co --2fe + 3co2m(fe)=56*81=4536 kg

The mass of 96% iron is 4536 96% = 4725 kg

ca(oh)2+2nh4cl=2nh3↑+2h2o+cacl210g10g

M can be known from the above relationship that this reaction is excessive Ca(OH)2, so it is directly calculated by NH4Cl:

x34=105m

The solution is m=3g

So, the amount of NH3 substance n=3 17

So, the volume of NH3 v=nx

x3÷17=

The third question solution ideas: from the second question, it can be seen that calcium hypochlorite reacts with concentrated hydrochloric acid to produce chlorine gas (the reaction belongs to the centering reaction), and concentrated hydrochloric acid will become dilute hydrochloric acid with the progress of the reaction, that is, it cannot continue to react with calcium hypochlorite to generate chlorine gas, but can only generate hypochlorous acid. From the volume of chlorine given in the question, the amount of HCl consumed can be calculated, and the amount of HCl consumed before the reaction can be subtracted from the amount of HCl consumed before the reaction, and the amount of HCl remaining when it no longer reacts with calcium hypochlorite to form chlorine gas (calculated:

The remaining n(HCl) = i.e. the concentration of the remaining hydrochloric acid is 5mol L

Which calculation problem? No question, what's the solution?

The conditions of this question may not be complete, and you need to know what the mass of "aluminum and magnesium of equal mass" is.

Suppose that the masses of "aluminum and magnesium of equal mass" are m, and write the chemical equation for the reaction of magnesium, aluminum, and hydrochloric acid to produce hydrogen, respectively.

The equation for magnesium is that magnesium produces one hydrogen, that is, magnesium added to 24 produces hydrogen with 2, and the actual mass added is (24-2) 24=11 12, which is 11m 12.

The equation of aluminum is that two aluminums produce three hydrogen, that is, 27*2=54 aluminum is added to produce 3*2=6 hydrogen, and the actual increase in mass is (54-6) 54=8 9, that is, 8m 9.

8m 9<11m 12, so you need to add aluminum on the aluminum side. Let the total mass of aluminium be m', then in order to balance the balance twice, 8m is required'/9=11m/12，m'=33m/32。However, aluminum with a mass of M has already been added, so a new mass of M needs to be added'-m=m32 of aluminum.

The final answer is to add aluminium of mass m 32 to one side of the aluminium, where m is the mass of the balance that has been added twice at the beginning.

Note: Since the goal of the question is to clarify a sufficient amount of dilute hydrochloric acid, it is assumed that aluminum and magnesium will react completely after being added

Although the mass of aluminum-magnesium added is equal, the amount of substance is not equal, so the quality of the hydrogen released after a complete reaction is not the same. So how much worse?

Let the masses of magnesium and aluminum be a, then a 24 the amount of magnesium that emits hydrogen.

a 27 The amount of aluminium is a 27*

Then the difference between the ends of the balance is a 18-a 24 amount of hydrogen. i.e. a 72 grams of aluminum into 27 grams of hydrogen is released, so a 8 grams of aluminum needs to be put in.

Add another 18 grams of magnesium to the right plate:

3mg+6hcl→3mgcl2+3h2

2al+6hcl→2alcl3+3h2

Equal hydrogen gas is generated.

The amount of magnesium required is: 3 24 = 72

The amount of aluminum required is: 2 27 = 54

Therefore, the amount of magnesium that needs to be added to the right disc is: 72-54 = 18g Basis: equal mass, and only hydrogen runs out in the end.

There are so many uncertainties. Is it completely reactive or is there an excess of metal? Otherwise, there is no way to do it.

In this world, it is impossible to find a specific quality.

Too much trouble to count.

I hate analytical chemistry the most ==

It is essential to know the excess or small amount of magnesium aluminum.

Fewer conditions. I don't know the quality, I can't count.

What is reduced is carbon dioxide and water vapor, which is 200-138 = 62 g2 NaHCO3 = = = Na2CO3 + CO2 + H2O168 (44 + 18).

x 62x=168g

1) Try to calculate the purity of baking soda in 168g of sodium bicarbonate in 200g sample (2) 168 200 = 84%.

(1) The amount of change in solids before and after the reaction of 2NaHCO3=Na2CO3+H2O+CO2 is.

x 200-138

x=2*84*(200-138) 62=168g(2)NaHCO3%=m(NaHCO3) m(total)=168 200=84%.

2.Solution: m(CO2)=100+ v=

Let the mass of caco3 participating in the reaction be x

CaCO3+2HCl===CaCl2+H2O+CO2 (gas mark).

x column proportional formula x=10g 10 12*100%= A:.

3.Solution: 160*80%=128t Let the mass of carbon monoxide be x

fe2o3+3co===2fe+3co2

128 x Column Proportional Solution x= Answer...

Fill in the blanks: 1Carbon dioxide, dry ice, rain enhancer.

2.Oxygen Oxygen Calcium carbonate Carbonic acid.

3.The clarified lime water becomes turbid Ca(OH)2+CO2==CaCO3+H2O, carbon dioxide gas.

4 Dry ice sublimates in the air to liquefy water vapor as a refrigerant.

5.Extinguish first No change first, then extinguish Density greater than air Does not support combustion Can not burn.

6.Ca(OH)2+CO2==CaCO3+H2O (precipitation number) CaCO3+2HCl===CaCl2+H2O+CO2 (gas standard).

Hope it helps! ~

Question 3 downstairs is wrong! ~

2. (1) CaCO3+2HCl==CaCl2+CO2 mass conservation It can be known that the weight of CO2 is m=

v=(2) From the chemical reaction, the ratio of CaCO3 to CO2 is 1:1, and the amount of CO2 is n=

Then the mass of caCO3 m=

Then the mass fraction of calcium carbonate in limestone = 10 12 =

3. The mass of Fe2O3+3CO==2Fe+3CO2Fe2O3 m=160*

Then the mass of CO m = 3 * (128 160) =

So at least tons.

Fill in the blank question 1, CO2, dry ice, refrigerant.

2. Oxygen, dry ice, calcium carbonate, carbonic acid.

3. White precipitate appears and a part of water will enter the test tube, CO2 + Ca(OH) 2 = = CaCO3 + H2O, and whether there is carbon dioxide in the gas.

4. Dry ice sublimation needs to absorb a lot of heat, which will lead to a decrease in the surrounding temperature. It is used as a fire extinguishing agent because dry ice sublimation has a cooling effect, and the CO2 generated has a flame retardant effect.

5. Extinguish first, then extinguish, do not support combustion, the density is greater than air, and it can flow 6, Ca(OH)2+CO2==CaCO3+H2O CaCO3+2HCl==H2O+CaCl2+CO2

Note: All equations generate CO2 with gas symbol ( ) It's hard to type to help you do it, adopt me.

Sodium carbonate reacts with hydrochloric acid to obtain sodium chloride, water and carbon dioxide (the chemical equation is written by yourself, to be balanced), sodium carbonate is calculated with grams of carbon dioxide, the solute of hydrochloric acid grinding is grams, and the generated sodium chloride is grams, so the original sodium chloride = grams = grams, so the total mass of sodium chloride after the reaction = grams = 65 grams, so the mass of the solution is 65 grams 13% = 500 grams, and the amount of solution before and after adding water is 200 grams, so the hydrochloric acid mass = 200 grams plus grams minus grams = 146 grams, Finally, the hydrochloric acid solute mass fraction = (g 146g)*100%=10%.

The equation is simple, and according to the mass of sodium carbonate, you can find the mass code of the original sodium chloride and the newly generated sodium chloride, a*13% = total mass of sodium chloride. The quality of hydrochloric acid is found according to sodium carbonate.

The solute mass in hydrochloric acid is.

hcl+naoh=nacl+h2o

x yx= y=

The amount of solute in solution.

2.The mass fraction of the solute in the resulting solution.

From the meaning of the title, the reaction equation NaOH + HCl = = NaCl + H2O. is used

Establish. The mass of solute in the NaOH solution is Xg, and the mass fraction of the solute in the resulting solution is WnaOH + HCl == NaCl + H2O

xg so, 40 x=, the solute mass in the NaOH solution is solved x = so the mass fraction of the solute in the resulting solution is w =