# Can you use calcium hydroxide instead of sodium hydroxide?

## in a precipitation reaction of CoCl2 and NaOH, can Calcium hydroxide be used in place of sodium hydroxide?

Feb 10, 2018

Yes, but the quantities would need to change

#### Explanation:

Start by writing out the reaction:
$C o C {l}_{2} + N a O H \to N a C l + C o {\left(O H\right)}_{2}$
Balance the reaction:
$C o C {l}_{2} + 2 N a O H \to 2 N a C l + C o {\left(O H\right)}_{2}$

Compare this to a reaction using $C a {\left(O H\right)}_{2}$:
$C a {\left(O H\right)}_{2} + C o C {l}_{2} \to C a C {l}_{2} + C o {\left(O H\right)}_{2}$
As you can see, only half the number of moles of the hydroxide compound is needed to bring the reaction to completion.