Question

balance the equation
ca(oh)₂ + hcl → cacl₂ + h₂o

Explanation:

Step1: Balance Ca atoms

There is 1 Ca atom on both sides. So, the coefficient for \(Ca(OH)_2\) and \(CaCl_2\) is 1.

Step2: Balance Cl atoms

In \(CaCl_2\), there are 2 Cl atoms. So, the coefficient for \(HCl\) is 2.

Step3: Balance H and O atoms

After setting \(HCl\) coefficient as 2, for \(H\) atoms: \(Ca(OH)_2\) has 2 H (from \(OH\)) and \(2HCl\) has 2 H. Total H on left is \(2 + 2=4\). On the right, in \(H_2O\), if coefficient of \(H_2O\) is 2, then H is \(2\times2 = 4\). For O: \(Ca(OH)_2\) has 2 O, and \(2H_2O\) has 2 O.

Answer:

1, 2, 1, 2