How easy is the alignment of chemical equations?

According to the conservation of valency, the conservation of atoms, and the conservation of mass, it will be easy and error-free. You may not be good at it at first, but if you do it a few times, you will become very proficient.

Chemical Equation Balancing: The equation of chemical reactions strictly adheres to the law of conservation of mass.

Tribal for redox reactions:

1.Mark the valency and calculate the amount of change in the valence;

2.Equal the total number of rises and falls in valence;

3.Then observe the number of metals in the non-redox part;

4.Finally, the number of hydrogen and oxygen is trimmed.

For redox reactions, the method of conservation of electrons can be adopted.

According to the substance obtained.

The number of electrons, equal.

The number of electrons lost.

The main thing is that the electrons gained and lost should be equal.

Here's how to trim a chemical equation:

1. Least common multiple method.

Applicable conditions: The original leased potatoes appear only once on the left and right sides of the equation, and this method is suitable for common chemical equations that are not very difficult.

2. Odd spouse law.

Applicable conditions: It is applicable to the multiple occurrences of an element on both sides of the chemical equation, and the total number of atoms of the element on both sides is odd and even.

3. Establish a law.

Applicable conditions: such as the reaction of most hydrocarbons or compounds containing hydrocarbon and oxygen to oxygen, as well as some decomposition reactions.

Fourth, the fraction balancing method.

This method can balance chemical reactions with elemental participation in the reaction or elemental generation. Specific steps:

1) first trim the atoms of each element in the compound;

2) equalize the atoms of elemental elements with fractions;

3) Remove the denominator so that the stoichiometric number after trim is an integer.

5. Algebraic method (also known as the method of undetermined coefficients).

Applicable conditions: There are many types of reactants or products, and the balance does not know where to start.

6. Observation balancing.

Applicable conditions: Sometimes there will be a substance with a complex chemical formula in the equation, and we can use this complex molecule to deduce the coefficients of other chemical formulas.

There is a law for balancing, but there is no definite law. For the same reaction equation, different methods may be used to balance, and sometimes even several methods may be used at the same time.

Sometimes there will be a substance with a complex chemical formula in the equation, we can deduce the coefficients of other chemical formulas through this complex molecule, for example: Fe + H2O Fe3O4 + H2, Fe3O4 chemical formula is more complex, obviously, Fe 3 in Fe ** in the elemental Fe, O comes from H2O, then Fe is preceded by 3, H2O is preceded by 4, then the formula is: 3Fe + 4H2O = Fe3O4 + H2 From this, the H2 coefficient is 4, and the conditions are written, ** can be changed to an equal sign:

3fe+4h2o(g)==fe3o4+4h2↑

It was easiest to balance with electronic gains.

It's easy to find the elements on both sides of the equation so that the number of the same elements on both sides is equal.

1. Trim chemical equation by least common multiple method.

First, find the number of the same atom on both sides and find the least common multiple. Divide the least common multiple by the number of atoms, which is the stoichiometric number that should be added before the chemical formula, and then balance the atoms of the other elements.

2. Observation method trim chemical equation.

First, find out the chemical formula with a more complex composition (more atoms) on both sides of the chemical equation, so that the metrometric number of the chemical formula is 1, and then determine the stoichiometric number (i.e. fraction) of other substances according to the conservation of the number of atoms, and then multiply a certain number on both sides of the equation to make each stoichiometric number the simplest integer.

3. Balance chemical equation by the undetermined coefficient method.

For some more complex chemical equations, the least common multiple method cannot be used, and it is difficult to use the observation method, so the undetermined coefficient method can be considered. With the undetermined coefficient method, not every chemical formula is preceded by an unknown, and the fewer the number of unknowns, the better.

1. Observation method: This method often works for some simple equations. In fact, even if the number is purposefully made up for balancing, there are often factors such as odd and even. This method is likely to work for any kind of equation.

2. Charge balance method: This method is most useful for ion equations. In the ionic equation, except for insoluble substances, gases, and water, everything else is written in ionic form, and the charges at both ends of the equation are equalized first, and then the observation method is used to balance water, gas, etc.

This method generally does not miss. But it's too good for redox equations.

3. Redox method: This method is for the redox equation. Remember here: "The valency rises and loses the redox agent". The corresponding is "reducing the valency to obtain a reducing oxidant". The specific usage is:

1) Mark the valency of the element in the upper part of the element where the valency of the element changes, and distinguish whose is higher and whose is lower.

2) Connect the same elements with lines to find and mark the number of higher charges or the number of lower charges.

3) Find the least common multiple and multiply it by the number of charges that increase or decrease, respectively.

4) Trim: Write the least common multiple of each before their respective chemical formulas (i.e., coefficients). And pay attention to whether these elements with valency changes are equal before and after the chemical change, and in general, if they are not equal, they are integer multiples.

5) Cooperate with the observation method to balance other good things such as water and insoluble matter generated.