How do you balance an equation (chemistry)?

Question

i REALLY dont get it.
we're doing it in class right now, but the professor isnt doing a very good job of explaining it, and the whole class is stumped.
for example, how would you balance this equation?
CaCl^2 + NaHCO^3 --> NaCl + Ca(OH)^2 + H2CO3
can someone please explain how to do this in general?
thanks in advance.

please please help me

Answer 1

You have to make sure there is an equal amount for each atomtype (C, O, Cl, ...) on each side of the equation.

So you have to find the right factors.
Usually you have to add something to the left side which might not be explicitly given:

for a watery environment : H2O
for an acid environment : H3O+
for a basic environment : OH-

You can balance the given equation by using the following method:

* First look at the 'easy' elements that only appear once on each side (Ca, Na and C) and assign variables to the factors you are looking for. (add water)

x CaCl2 + y NaHCO3 + z H2O --> y NaCl + x Ca(OH)2 + y H2CO3

The variables in the right hand side come from Na, Ca and C respectively.

Then look at the other elements:
Cl --> 2x = y

H --> 2x + 2z = 2x + 4x -> z = 2x

O --> 8x = 8x --> OK

Taking x = 1 gives whole numbers (y=z=2)

1 CaCl2 + 2 NaHCO3 + 2 H2O --> 2 NaCl + 1 Ca(OH)2 + 2 H2CO3

Answer 2

Your equation needs corrections, because you can not make a stronger base Ca(OH)2 and an acid H2CO3 from a weaker base NaHCO3 and a salt CaCl2.

CaCl^2 + NaHCO^3 --> NaCl + Ca(OH)^2 + H2CO3
should be
CaCl^2 + NaHCO3 --> NaCl + Ca(HCO3)2

How to balance it?
This is a double-replacement reaction. You can do it one element at a time. For example, you start with Ca element which is balanced. Then move on to Cl element. There are two Cl in CaCl2 but only one Cl in NaCl. So you need 2 in front of NaCl to balance Cl element. Now you look at Na. You need 2 in fron of NaHCO3 in order to balance Na. Finally you exam if H, C, O are balanced, which are.

So the balanced euqation is

CaCl^2 + 2NaHCO^3 --> 2NaCl + Ca(HCO3)2

Answer 3

To balance the equation, you must have the same number of atoms of any species on both side of the equation

Take your case

in Ca Cl2, you have 2 atomes of chlorine on the left side. So, you must have two atoms of Cl on the right side. On the right side, you have only Cl in Na Cl. So ,there must be two molecules of

Na Cl which are formed . for Na and H the same you must put a factor 2 before NaHCO3

so, the result

CaCl2 +2 Na HCO3 --> 2Na Cl +Ca (OH)2 +2 HCO3



To balance your equation

Answer 4

Al + O --> Al2O3
is a better idea as an example, you can clearly see that you have two Al on the right hand side, so you need two on the left. Similarly for oxygen - you have three on the right so you need three on the left. Since oxygen comes in pairs, it balances to
4Al + 3O2 --> 2Al2O3
I said that is a better example because - unless I've made a mistake - yours can't be balanced!

Answer 5

Ca2Cl^2 + NaH2CO^3 --> NaCl + Ca(OH)-^2 + H2CO3 this is a displacement reaction to make it easy the calcium wants the hydrogen and gets it leavin hydrogen plus carbon dioxide now its balenced

Answer 6

you have to make sure each side has the same number of each element.

Your equation has 2 Cl on the left, but only 1 on the right. You need to have 2 (the same number) on both sides. So, change the right to 2 NaCl.
Now, you have 2 Na on the right, but only 1 on the left. So, change the left to 2 NaHCO3. Et cetera. Continue until ALL elements balance on both sides.


Oh, and you need to add a H2O to the left. Won't balance without it.

Answer 7

the way to balance chemistry is easy CaCl2 + NaHCO3 --> NaCl + H2CO3 . the first half will equal the second half . an example is 2H2O --> 2H2 + O2

Answer 8

The atoms of one spacey of on side must be equal with the atoms of the same tip on the other side. It says that the number of atoms that enters in a reaction remain the same.

Answer 9

This is such a bad question as all the reactants and 'products' are all soluble in water and they all exists as ions floating around: unless you have copied the question incorrectly. Even when they are in the solid state, the products are not as stated.

Answer 10

you can't balance this one because your only source of CO3 and H are coming from your reactant side from the NaHCO3 and your product side has a different proportion of H2CO3