# Chemistry Balancing

posted by .

To balance an equation

For example

if the equation was

CaOH2 + HCl ---> CaCl2 + H20

the question is , if i want to balance , should i count the OH ( hydroxide ) as a whole thing or separately so the O goes with the other oxygens and the H goes with the other hydrogens

can someone explain how can i balance the whole equation

thanks

• Chemistry Balancing -

The proper way to write calcium hydroxide is Ca(OH)2, not CaOH2. The O and H atoms in the OH- ionic part of the molecule remain close to one another and transfer as a pair in chemical reactions or when dissolved in solutions. The reaction you are trying to balance is a neutralization with the acid HCl. Each HCl atom gives up one H+ ion in the reaction, and it combines with one OH- from the base to form an H2O (or HOH) molecule. Ca(OH)2 contains two OH- ions, so it takes two HCl molecules to neutralize each Ca(OH)2 molecule.

Therefore the balanced reaction is in this case
Ca(OH)2 + 2 HCl = CaCl2 + 2 H2O

• Chemistry Balancing -

don't understand !

• Chemistry Balancing -

Mary,
The point is that you need the parentheses to show that it is two OH- ions in Ca(OH)2
like
OH Ca OH
not
H Ca OH
Maybe it would be easier if you wrote it as two separate reactions
Ca++ + 2 Cl- ---> CaCl2
2 H+ + 2 (OH)- ---> 2 H2O
Ca++ + 2 (OH)- + 2 H+ + 2 Cl- ---> CaCl2 + 2 H2O
You would not really write it this way but perhaps it makes it easier to see how the ions combine. The calcium ions grab the chlorine ions to make the salt CaCl2 and the hydrogen and hydroxide ions are left in solution to form water.

• Chemistry Balancing -

Yet another way to look at it.
Three points here.
First, Ca has a valence of +2.
OH, as a unit, has a valnece of -1.
Therefore, it takes two OH units at -1 to balance the charge on Ca at +2. We writre the symbol for calcium hydroxide as Ca(OH)2.

Second point. If you write CaOH2, it means, by definition, that we have 1 Ca, 1 O and 2H atoms. That isn't what we want for the OH is -1 (not O and H2 a -1). If we want to show that the ENTIRE OH part is used and we want two of them, we write (OH)2. When parentheses are used, everything inside the parentheses are multiplied by 2. Thus OH2 means 1 O and 2 H atoms, but (OH)2 means 2O and 2 H atoms. By writing the symbol for calcium hydroxide as Ca(OH)2, we see that Ca at +2 and OH as -1 each gives us a total of +2 charge and that equals the -2 charge.

Third point. Writing a cryptic note that you don't understand tells us almost nothing about what your problem is. The three of us have TRIED to understand, each taking a different tack to explaining what we think you don't understand. Perhaps one of us hit the mark, perhaps none of us did. If you still don't understand, please explain in detail what your problem is and we can take it from there. Otherwise, we are stumbling in the dark as we try to guess.

## Similar Questions

1. ### Chemistry

hi I'm having a serious problem with balancing chemical equations , can someone explain to me how we can do them also if i had a word equation hhow can i convert it into a symbolic equation and balance it e.g can someone show me how …
2. ### Chemistry

hi I'm having a serious problem with balancing chemical equations , can someone explain to me how we can do them also if i had a word equation hhow can i convert it into a symbolic equation and balance it e.g can someone show me how …
3. ### Chemistry+balancing equation tips

We are on combustion reaction at the moment in chemistry, and I have to say, these reactions are like extremely hard to balance(well, just alot of erasing). It takes me a while to balance combustion reactions and I want to know if …
4. ### chemistry

Balance equation for reaction occuring in basic solution. CrO4{2-}+S{2-}gives S+CrO{-} i don't know how to balance the charges in this way of balancing please teach me how to do it?
5. ### CHemistry

Redox equations are often long and difficult to balance by inspection. Luckily, electron transfers and oxidation numbers provide hints for balancing such equations. Balance the following equation: K2CrO4 + Na2SO3 + HCl ---> KCl …
6. ### Chemistry

Need help balancing this equation, just the coeffecients, do not need to balance the charges. The numbers are subscripts: Ca0.41Mg0.36Mn0.50Fe1.76Al2Si3O12 + H + H20 <---> Al(OH)3 + FeOOH + MnO2 + Ca + Mg + Si(OH)4
7. ### chemistry(balance equation)

hi!i am a f4 student in hk.i have know the basic concept of balance equation.but some too complex equation i cant balance.is there any general short cut for balancing any simple or complex chemical equation?
8. ### Chemistry

I don't quite understand why this isn't balanced and what we'd have to do to balance it and why. If someone could explain in-depth I would appreciate it. Balance this equation: C2H5OH(l) + O2(g) >>>>> CO2(g) +H20(g)
9. ### chemistry

don't quite understand why this isn't balanced and what we'd have to do to balance it and why. If someone could explain in-depth I would appreciate it. Balance this equation: C2H5OH(l) + O2(g) >>>>> CO2(g) +H20(g) Show …
10. ### Chemistry

After balancing the following redox equation(using small whole-number coefficients), add the coefficients of all species in the balanced equation. Bi(OH)3 + SnO2^(2-) → Bi + SnO3^(2-) (basic solution) --- I separated the equation …

More Similar Questions