Question

How would you complete and balance the acid base neutralizations reaction: `HBr + Ba(OH)_2 ->`?

Answer 1

`2"HBr" + "Ba(OH)"_2 -> "BaBr"_2 + 2 "H"_2"O"`

Explanation:

In a neutralization reaction, if the base is a hydroxide, then the products formed would be the salt and water.

acid + base `->` salt + water

The water (`"H"_2"O"`) is a result of the combination of the `"H"^+` from the acid and the `"OH"^-` from the base.

The salt (`"BaBr"_2`) is simply the remaining anion of the acid (`"Br"^-`) and the cation of the base (`"Ba"^{2+}`).

The unbalanced equation is therefore

`"HBr" + "Ba(OH)"_2 -> "BaBr"_2 + "H"_2"O"`

To balance the equation, first notice that the number of Ba on both sides are the same. Ba is balanced.

Next, notice that the LHS is short of 1 x Br. So balance it by adding 1 unit of HBr.

`"2HBr" + "Ba(OH)"_2 -> "BaBr"_2 + "H"_2"O"`

Now, the RHS is missing 2 x H and 1 x O. Balance that by adding 1 units of `"H"_2"O"`.

`"2HBr" + "Ba(OH)"_2 -> "BaBr"_2 + 2"H"_2"O"`

Now, all the elements have equal amounts on both sides of the equation. The chemical equation is now considered balanced.