Simple calculations using chemical equations in exercises 2, 3, and 4

2, C2H4+3O2===2CO2+2H2O There are many ways to balance, there are more than 10 kinds, and this problem is more convenient for the odd and even method.

2NaOH+CuSO4===Cu(OH)2 +Na2SO4 displacement reaction, this is very easy to match.

Fe2O3+3H2===2Fe+3H2O Reduction of hydrogen, the least common multiple can be done.

2Fe2O3+6CO===4Fe+3CO2 reduction of carbon monoxide, least common multiple.

3, ch4+2o2===CO2+2H2O write according to the title, and then trim zn+H2SO4===znSO4+H2 according to the title, no need to trim, it's very simple.!

4. Calculation of equations:

Set: Cuo y gram is required.

h2+cuo===h2o+cu

y 3g 80：64=y:3 y=

Purely manual operation! Hope, thank you!

c2h4+3o2=2co2+2h2o

2NaOH+CUSO4-=Cu(OH)2 +Na2SO4FE2O3+3H2=(High Temperature)2FE+3H2OFE2O3+3Co=(High Temperature)2Fe+3CO2CH4+2O2=(Ignite) CO2+2H2O

zn+h2so4=znso4+h2↑

h2 + cuo = cu + h2o

x80/x=64/

The solution is x=

1） d.

2.Trim the following chemical equations.

1) C2H4+3 O2---2 CO2+2 H2O2)2 NaOH+CuSO4---Cu(OH)2 +Na2SO43)Fe2O3+3 H2--- High Temperature ---2 Fe+3 H2O4)Fe2O3+3 CO--- High Temperature ---2 Fe+3 CO23Zinc reacts with hydrochloric acid (HCl) to produce hydrogen and zinc chloride. What is the mass of hydrogen and zinc chloride that can be produced by using zinc in the laboratory to react with a sufficient amount of hydrochloric acid?

zn+ 2 hcl= h2 + zncl2x y

x= y=

1d 2b 3d

Do your own calculations according to the chemical equations, just start learning chemistry Don't be lazy.

2. A factory needs 100 kg of oxygen as raw materials. If this oxygen is produced by electrolysis of water, what is the quality of the water consumed? What is the mass of hydrogen that can be obtained at the same time?

3. Zinc reacts with hydrochloric acid to produce hydrogen and zinc chloride. In the laboratory, gram of zinc is reacted with a sufficient amount of hydrochloric acid, and what is the amount of hydrogen and zinc chloride that can be produced?

x y 100kg

x=y=3, laughing game excavation: let the amount of wax that can be produced for hydrogen and zinc chloride be x, yzn + 2HCL = ZNCL2 + H2 y x

x=y=

Volume is volume ratio.

For example, you can see that 560L of ammonia is soluble in 1L of water under standard conditions, and introduce a value in the question, so that the problem is very good.

Also, is the title wrong? What is the density of ammonia? Is it the density of ammonia?

According to the density of ammonia: the amount of ammonia substance is 560

The quality of ammonia is 25*17+1000=1425g

Ammonia volume 1425 (

The amount of ammonia substance concentration 25

1. The volume can be 1 cubic centimeter, 1 cubic decimeter, or 1 cubic meter.

The volume of question 1 is 1L

The mass of ammonia is 25 * 17 + 1000 = 1425g The density of ammonia is.

The volume of ammonia is 1425 900=

The concentration of the substance of ammonia is 25

The 1 volume here is water, not a solution, which must be noted.

This kind of question, do it with definitions.

Let 1 volume be 1L

c=n/v=(560/

1 volume, you can think of it as 1l, as long as the volume ratio of ammonia to water does not change, it has no effect on the result.

c=1000ρw%/m

w%=560*17 (560*17+1000)*100%=so c=1000*

The meaning here is that the specific volume of the reactants is not given, but the specific ratio of the reactants is given, and we can calculate the ratio of the amount of ammonia to the volume of water.

In fact, the general question says that a volume, and you can directly bring it in with 1 liter (1L), because the questioner calculates that this question has nothing to do with giving a specific volume, it is a fixed value.

In other words, it should be the density of ammonia or the unit is wrong, how can the density of ammonia alone be so high...

Because 560 volumes of ammonia are dissolved in 1 volume of water, the volume will also change, so it cannot be calculated from n v

Here "560 volumes of ammonia dissolved in 1 volume of water" refers to the ratio of ammonia to water is 560:1

There is no emphasis on specific units.

Zn + H2SO4 == ZnSO4 + H2 hydrogen volume.

2kClO3 = 2kCl + 3O2 before and after difference = gas mass! ==o2 mass=

2*(39+ KCl mass.)

2*(39+ mass of potassium chlorate.)

c+d=a+d？？？

The answer in the question is incorrect.

Only HCl, which produces chlorine Cl2, is oxidized. The formation of KCl and CrCl3 is not considered to be oxidized.

As can be seen from the chemical reaction equation, only 6 of the 14 chloride ions are oxidized to chlorine atoms.

So it's calculated like this.

The parentheses (14*) are changed to (substitute data, m2=