How do you balance chemical equations?

Answer 1

chemical equation describes what happens in a chemical reaction. The equation identifies the reactants (starting materials) and products (resulting substance), the formulas of the participants, the phases of the participants (solid, liquid, gas), and the amount of each substance. Balancing a chemical equation refers to establishing the mathematical relationship between the quantity of reactants and products. The quantities are expressed as grams or moles.
It takes practice to be able to write balanced equations. There are essentially three steps to the process:

Write the unbalanced equation.
Chemical formulas of reactants are listed on the lefthand side of the equation.
Products are listed on the righthand side of the equation.
Reactants and products are separated by putting an arrow between them to show the direction of the reaction.
Reactions at equilibrium will have arrows facing both directions.
Balance the equation.
Apply the Law of Conservation of Mass to get the same number of atoms of every element on each side of the equation. Tip: Start by balancing an element that appears in only one reactant and product.
Once one element is balanced, proceed to balance another, and another, until all elements are balanced.
Balance chemical formulas by placing coefficients in front of them. Do not add subscripts, because this will change the formulas.
Indicate the states of matter of the reactants and products.
Use (g) for gaseous substances.
Use (s) for solids.
Use (l) for liquids.
Use (aq) for species in solution in water.
Write the state of matter immediately following the formula of the substance it describes.

Answer 2

That's a pretty vague question "as is"...

For some reactions, it's a mere trial-and-error process. Or as we say in the trade, you balance "by inspection". You adjust this coefficient, then that one, until finally, the same number of moles of each atom appear (tho' perhaps in different combinations) on the left and right sides of the equation.

Some more specialized reactions, such as those that depict an oxidation-reduction process, have limitations and special conditions which must hold true in order for it to be TRULY balanced. In the case of oxidation-reduction, the number of electrons gained must equal the number of electrons lost. In such cases, the equation when balanced by inspection CAN be INCORRECT; one must adjust coefficients to account for electron balance or "charge balance" as well as to balance the stoichiometry (or mass balance.)

Without further information, this is about all we can do for you.
Come back when you're a bit more read up on what you'd like to do.

Answer 3

Taking an example.

H2 +Cl2 = 2HCl

In 'H2' there is one (1) molecule of hydrogen containing 2 atoms of hydrogen.

Similarly in 'Cl2' there is one(1) molecule of chlorine containing two atoms.

So all together there are 4 atoms. to react.

NB Atoms CANNOT be made or destroyed in a reaction.

The product contains two(2) molecules of hydrogen chloride. Each molecule contains two atoms - one of hydrogen and one of chlorine. Altogether in the products there are four atoms.

Another example.
CH4 + O2 = CO2 + H2O
This is a unbalanced equation.
Notice on the reactant side there is one(1) carbon
On the product side there is also (1) carbon - balanced.

Also on the reactant side there is 4 hydrogens.
On the product side there is only two(2) hydrogens.
So to make four hydrogens on the product side a '2' is placed in front of the 'H2O'. - H's balanced.

So far:- CH4 + O2 = CO2 + 2H2O

This is still unbalanced.
Notice there are 4 oxygens on the product side, but only 2 on the reactant side.
So to make 4 oxygens on the reactant side a '2' is placed in front of the oxygen molecule.

So the balanced reacttion is : -

CH4 + 2O2 = CO2 + 2H2O

Answer 4

Here's a really simple example:

Unbalanced: H + O -> H2O
As you can see from the above, we have gained a Hydrogen atom from somewhere.

Balanced: 2H + O -> H2O
By specifying 2H, nothing has been gained or lost either side.

This is still not quite correct though, because Hydrogen and Oxygen will be in pairs. so the balancing becomes more difficult.

O2 + H2 -> H2 O

Becomes:

O2 + 2(H2) -> 2(H2O)

Make any sense?

Answer 5

well I can surely teach u here but u will not get them. YOU really need to go through the examples first. read the text and above all u can search on net for it... type .. Balancing Equations Chemistry. tht will really help u. m sorry i cant provide any links right now.

Answer 6

The number of atoms of EACH reactant ELEMENT MUST equal the number of atoms of EACH product ELEMENT

(Matter cannot be created or destroyed but can be converted into other forms. i.e. the total weight of Reactants must equal the total weight of Products).

Simple e.g.

CH4 + 2O2 = CO2 + 2H2O (Complete combustion)
----------------------------------------------------------------------
Reactants: (at.wts): C = 12: H = 1 (H4 = 1 x 4 =4):
O = 16 (2O2 = 64).

Totals C = 12: H = 4: O = 64.
------------------------------------------------------------------------
Products: (at.wts): C = 12: O (in CO2) = 16 x 2 = 32
H (in water) = 1 x 4 = 4: O (in water) = 16 x 2 = 32.

Totals: C = 12: H = 4: O = 64.

Equation is balanced:

Answer 7

H2 + Br2 = HBr & HBr You have to make sure that there is the same amount of elements on each side of the equation. so for this equation it makes 2 molecules of HBr because ther are 2 of each element on the other side of the equation.

Answer 8

the amount of atoms on the right must equal the amount on the left. count up the amount of atoms for each element and they should equal that amount on both sides.

Answer 9

Its just like algebra. You simplify both sides of the equation like this. (this is not a real compound.)

AB+2AABT, B+3AP+2T =5A+3B+2T, B+3A+3P+2T= 2A+2B,3P

If memory serves me. I'm probably wrong though.