[formaldehyde]

So I'm conducting an investigation to see the affect on the rate of reaction between reacting different concentrations of Hydrochloric acid and Sodium Carbonate (anhydrous).

I was given a 1 molar solution of HCl to start with and I will have to dilute it to lower concentrations for this investigation.

This is where I got stuck: I tried using the formulas:
 
concentration = moles/volume

and

molarity = moles/liter.

I have no idea how. Could anyone please shed light on this? It would be highly appreciated.

[Nat360]

So for a dilution, you want to use the dilution formula as shown below.

C₁V₁=C₂V₂

Where:
C₁ is the initial concentration
V₁ is the initial volume
C₂ is the desired concentration or final concentration
V₂ is the final volume needed to reach C₂

So in your scenario, the 1 molar solution of HCl is your C₁. Your initial volume is how much of the HCl is going to be used. C₂ is the final concentration you want. Then you substitute the values into the equation and solve for V₂, which is now the total volume needed to get to a concentration of C₂.

Now to find how much water is needed to dilute HCl, you just do V₂ - V₁. That would give you the amount of water needed to reach C₂ from the original volume.

Hope that helps.
Please correct me if I have done anything wrong.

[Borek]

This is basically mass conservation: whatever you put in the solution, stays there.